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PubMed2005

A training program for certified asthma educators: assessing performance.

BACKGROUND: Evidence-based asthma guidelines identify asthma education as an essential element of care. In Canada, a process for certifying asthma educators was established to help provide asthma education to patients. A critical component to certifying asthma educators is their training and evaluation. The purpose of the study was to identify an approach to evaluate participants and to determine if specific characteristics influenced participants' success. METHODS: Participants completed a questionnaire that collected demographic, practice, and learner characteristics. Assessment strategies and criteria used to determine the level of success included 1) a written asthma knowledge score; 2) a written educational theory score, and 3) a practice teaching skill score based on three encounters with standardized patients. Standardized patient encounters were scored by using a standard checklist of essential teaching functions. RESULTS: Participants (n = 73) represented a broad range of health professions (respiratory therapists, nurses, pharmacists, and physiotherapists). The average score for written asthma knowledge, educational theory, and practice skill assessment was 82.0 +/- 8.0%, 68.6 +/- 16.2%, and 80.3 +/- 9.7%, respectively. Moderate interrelationships were observed between the practice teaching skills score and years of practice in asthma (r = 0.35; p < 0.01) and percentage of workdays dedicated to asthma care (r = 0.30; p < 0.05). Moderately strong relationships were observed among the three standardized patient encounters. However, there were no associations between participant scores on the written asthma or educational theory examination and the practice skill assessment scores. CONCLUSIONS: Participants of an asthma educator training program represent a wide range of disciplines, practice settings, and experience. It is important that asthma educator training programs assess both written knowledge and practice assessments to evaluate participants.

Adult↗

PubMed1983

Evidence for an intron-contained sequence required for the splicing of yeast RNA polymerase II transcripts.

We constructed numerous deletion mutants in the 3' region of the yeast actin gene intron. When these were introduced into yeast on autonomously replicating shuttle vectors, a sequence element between 35 and 70 nucleotides upstream from the 3' splice site was required for splicing the actin gene transcripts. In mutant genes where this intron region was maintained but new sequences introduced immediately downstream replaced the normal 3' acceptor site sequences, alternative splicing occurred. The alternative splicing signal was generally the first AG dinucleotide following the intron sequence required for splicing. The intron-contained sequence is sufficient to define new intron-exon boundaries. It contains the octanucleotide 5'-TACTAACA-3', which occurs 20 to 55 nucleotides upstream from the 3' splice site in all split protein-coding nuclear genes from S. cerevisiae sequenced to date, and we suggest that it is an essential element of the yeast splicing mechanism, involved in the selection of splicing sites.

Base Sequence↗

PubMed2006

Transcription of human zinc finger ZNF268 gene requires an intragenic promoter element.

Human ZNF268 gene is a typical Krüppel-associated box/C2H2 zinc finger gene whose homolog has been found only in higher mammals and not in lower mammals such as mouse. Its expression profiles have suggested that it plays a role in the differentiation of blood cells during early human embryonic development and the pathogenesis of leukemia. To gain additional insight into the molecular mechanisms controlling the expression of the ZNF268 gene and to provide the necessary tools for further genetic studies of leukemia, we have mapped the 5'-end of the human ZNF268 mRNA by reverse transcription-PCR and primer extension assays. We then cloned the 5'-flanking genomic DNA containing the putative ZNF268 gene promoter and analyzed its function in several different human and mouse tissue culture cell lines. Interestingly, our studies show that the ZNF268 gene lacks a typical eukaryotic promoter that is present upstream of the transcription start site and directs a basal level of transcription. Instead, the functional promoter requires an essential element that is located within the first exon of the gene. Deletion and mutational analysis reveals the requirement for a cAMP response-element-binding protein (CREB)-binding site within this element for promoter function. Gel mobility shift and chromatin immunoprecipitation assays confirm that CREB-2 binds to the site in vitro and in vivo. Furthermore, overexpression of CREB-2 enhances the promoter activity. These results demonstrate that the human ZNF268 gene promoter is atypical and requires an intragenic element located within the first exon that mediates the effect of CREB for its activity.

5' Flanking Region↗

PubMed1975

Function and homeostasis of copper and zinc in mammals.

Recently there has been great interest in the determination of levels of trace elements in biological systems. The goals of many researchers in this field have been: understanding the roles of micronutrients in biochemical processes and the evaluation of biological mechanisms that maintain tissue concentrations at relatively constants levels. The biochemical and physiological functions of the micronutrients copper and zinc have been reviewed with emphasis on factors, both endogenous and exogenous, associated with the maintenance of homeostatic levels in mammalian sera. Understanding the mechanisms affecting homeostasis will provide a background necessary for the application of data on serum trace minerals in the diagnosis and prognosis of disease states. The general roles of copper and zinc in animal nutrition may be understood by evaluating physiologic changes associated with deficiency states of these essential elements. Deficiencies are associated with antagonisms and interactions from other elements and from chelating organic compounds as well as with primary deficiencies due to insufficient dietary levels. Biochemical and physiochemical properties of copper and zinc biomolecules are discussed with primary emphasis on the forms of these metals in serum. Also discussed in detail, are the effects of disease, radiation exposure and environmental factors on serum and tissue copper and zinc levels.

Animals↗

PubMed1990

Quantitative analysis of the glucocorticoid receptor-DNA interaction at the mouse mammary tumor virus glucocorticoid response element.

Purified glucocorticoid receptor (GR) from rat liver was used for a quantitative analysis of the protein-DNA interaction at specific GR-binding segments within the 5'-long terminal repeat of the mouse mammary tumor virus. A truncated receptor was generated and used to demonstrate formation of heterodimeric GR, which furthermore was shown to be in rapid equilibrium with receptor-monomer. The relative affinity for GR binding to specific GR sites versus random calf thymus DNA was approximately 2 x 10(3). At equilibrium a free GR concentration of 3 x 10(-10) M was required for half-maximal saturation of the two functionally important DNA sites within the mouse mammary tumor virus 5'-long terminal repeat. Although these two DNA segments act synergistically in mediating hormonal response, we did not detect cooperative GR binding to these regions in vitro. However, GR bound cooperatively within the downstream binding region. Similarly, GR was unable to facilitate factor binding to a neighboring nuclear factor 1 site, another essential element in the promoter. In contrast, nuclear factor 1 binding was inhibited slightly by GR.

Animals↗

PubMed2003

Specific inactivation of isomerohydrolase activity by 11-cis-retinoids.

The endergonic trans-->cis isomerization of retinoids is an essential element in rhodopsin regeneration in vertebrates. All-trans-retinyl esters, which are generated by lecithin retinol acyltransferase (LRAT), are on the isomerization pathway. The critical isomerohydrolase activity, which catalyzes the trans-->cis isomerization/hydrolysis reaction of all-trans-retinyl esters, remains to be identified. It is demonstrated here that 11-cis-retinyl bromoacetate (cRBA) is a potent and specific inactivator of the bovine retinyl pigment epithelial (RPE) isomerohydrolase activity, with a measured K(I)=0.19 microM and a pseudo-first-order rate of inactivation k(inh)=1.83 x 10(-3) s(-1). This demonstrates that the isomerization is indeed enzyme-mediated. This inactivator should facilitate the identification and study of isomerohydrolase, or at least an essential component of it. Labeling of crude RPE membranes with 3H-cRBA reveals the presence of several labeled bands that may be isomerohydrolase candidates.

Acyltransferases↗

PubMed2005

The nuclear receptors constitutive androstane receptor and pregnane X receptor cross-talk with hepatic nuclear factor 4alpha to synergistically activate the human CYP2C9 promoter.

CYP2C9 is an important human drug-metabolizing enzyme that is expressed primarily in liver. Recent studies in our laboratory have shown that the nuclear receptor pregnane X receptor (PXR) is important in the transcriptional activation of the CYP2C9 promoter by drugs such as rifampicin and that the essential element is a constitutive androstane receptor (CAR)/PXR site -1839 bp upstream of the translation start site. Both CAR and PXR transcriptionally up-regulate the CYP2C9 promoter via these elements. In the present study, we ask whether additional sites in the proximal promoter also play a role in this induction. We identify two proximal hepatic nuclear factor (HNF) 4alpha binding sites at -152 and -185 bp of the CYP2C9 promoter, both of which bind HNF4alpha in gel shift assays and transcriptionally up-regulate this promoter in response to HNF4alpha in HepG2 cells. HNF4alpha synergizes with CAR and with PXR in HepG2 cells treated with rifampicin. The synergy only occurs when the CAR/PXR binding site at -1839 bp is present. Mutation of the two HNF4alpha binding sites differentially prevented up-regulation of CYP2C9 promoter by both CAR as well as HNF4alpha, synergy between the two receptors, and essentially abolished induction by rifampicin in HepG2 cells transfected with PXR. These studies strongly support the hypothesis that there is cross talk between distal CAR/PXR sites and HNF4alpha binding sites in the CYP2C9 promoter and that the HNF4alpha sites are required for maximal induction of the CYP2C9 promoter.

Aryl Hydrocarbon Hydroxylases↗

PubMed1996

Processing of mammalian rRNA precursors at the 3' end of 18S rRNA. Identification of cis-acting signals suggests the involvement of U13 small nucleolar RNA.

Molecular mechanisms involved in the nucleolytic cleavage at the 18S rRNA/internal transcribed spacer 1 (ITS 1) junction, a late step of small-subunit pre-rRNA processing in vertebrates, remain largely unknown, mostly due to the lack of faithful in vitro assays. To identify the minimal cis-acting signals required for this reaction, we studied the processing of truncated human rRNA gene transcripts transiently expressed upon transfection of rRNA minigenes into cultured mouse cells. We observed that processing at this site was faithfully reproduced with transcripts containing only 60 nucleotides of 18S rRNA and the adjacent 103 nucleotides of ITS 1, but was abolished or severely altered by further shortening of either sequence. Remarkably, this minimal transcript contains, within its 18S rRNA part, long sequences complementary to both U20 and U13 small nucleolar RNAs (snoRNAs). The cis-acting elements essential for the reaction were studied further by site-directed mutagenesis. The U20 snoRNA complementary region in 18S rRNA was not required for faithful processing at the 18S rRNA/ITS 1 junction. Also, processing at this site was not appreciably altered by random substitution of proximal ITS 1 sequences (including the 5' terminal nucleotide) or of the terminal nucleotide of mature 18S rRNA. Substitutions in the four-nucleotide loop of the 18S rRNA 3'-terminal stem-loop, including the two adenosine residues substrates of dimethylation, did not alter appreciably the formation of the 18S rRNA 3' end, showing that the (methyl)2A1850.(methyl)2A1851 doublet was not required for processing at this site. Two highly conserved 18S rRNA elements acted as major cis-acting signals for processing at the 3' end, the CAUU sequence immediately preceding the 3'-terminal nucleotide and the 3' strand of the 3'-terminal 18S rRNA helix, complementary to U13 snoRNA. Compensatory mutations, restoring the potential for helix formation, but not U13 snoRNA complementarity, did not restitute the cleavage at the 3' end of 18S rRNA. This suggests that U13 snoRNA may be a trans-acting factor in the nucleolytic cleavage at the 3' end of 18S rRNA.

Animals↗

PubMed1995

Involvement of SOX proteins in lens-specific activation of crystallin genes.

We have studied the mechanism of delta 1-crystallin gene activation, which occurs early in lens cell differentiation, and have previously shown that an essential element of the delta 1-crystallin enhancer is bound by a group of nuclear factors, delta EF2, among which delta EF2a is highly enriched in lens cells. In this report we show that the cDNA of delta EF2a codes for the chicken SOX-2 protein (cSOX-2), which is structurally related to the sex-determining factor SRY. Sox-2 is expressed at high levels in the early developing lens in both chicken and mouse embryos. Overexpression of delta EF2a/cSOX-2 increased delta 1-crystallin enhancer activity to a plateau in lens cells, but not in fibroblasts, consistent with the previously drawn conclusion that delta EF2a activates transcription only in concert with another factor present in the lens. This result supports the model that SOX proteins act as architectural components in the activating complex formed on an enhancer, as indicated for another HMG domain protein, lymphoid enhancer binding factor 1 (LEF-1). We also show that SOX protein binding is essential for lens-specific promoter activity of the mouse gamma F-crystallin gene. This work is the first to show delta- and gamma-crystallin genes as examples of direct regulatory targets of SOX proteins and provides evidence that diversified crystallin genes are regulated, at least partly, by a common mechanism.

Amino Acid Sequence↗

PubMed1989

Combined nephrotoxicity of methylmercury, lead, and cadmium in Pekin ducks: metallothionein, metal interactions, and histopathology.

This report describes the metallothionein (MT) levels and accumulation of mercury, lead, and cadmium, as well as their interaction with tissue zinc, copper, and iron, and the histopathological changes in kidneys of ducks exposed to methylmercury chloride (MeHgCl), lead acetate (PbAc), and cadmium chloride (CdCl2), singly or in combination for 13 wk. Forty-eight female Pekin ducks, divided into 8 groups of 6 birds each, were fed diets containing no added metals (control), 8 mg MeHgCl/kg feed, 80 mg PbAc/kg feed, 80 mg CdCl2/kg feed, 8 mg MeHgCl + 80 mg PbAc/kg feed, 8 mg MeHgCl + 80 mg CdCL2/kg feed, 80 mg PbAc + 80 mg CdCl2/kg feed, and 8 mg MeHgCl + 80 mg PbAc + 80 mg CdCL2/kg feed. Cadmium (Cd) when administered alone or in combination caused a 60-fold increase in kidney MT levels, while methylmercury (MeHg) or lead (Pb) administration caused a threefold increase in kidney MT levels. No significant changes in kidney MT levels were observed when metals were administered concurrently when compared with single-treatment groups. Residue analysis revealed accumulation of administered metals in kidney tissue. However, lead administration resulted in accumulation of small amounts of this element in kidney tissue. Simultaneous administration of MeHgCl and PbAc significantly increased the accumulation of lead in kidney when compared with PbAc-treated group. Cadmium when administered alone or in combination caused an increase in the levels of zinc and copper in kidney. Administration of MeHgCl or PbAc either alone or in combination caused increased iron levels in kidney, while cadmium administration either alone or in combination caused decreased iron levels. Administration of cadmium either alone or in combination caused degenerative changes in kidney proximal tubules. The severity of degenerative lesions increased when cadmium was simultaneously administered with other metals. These results indicate that combined administration of MeHg, Pb, and Cd has no significant effect on kidney MT levels or on essential elements in kidney tissue when compared with single metal groups. However, there appears to be an increase in the severity of histopathologic changes.

Animals↗

PubMed1999

Pneumolysin, a protein toxin of Streptococcus pneumoniae, induces nitric oxide production from macrophages.

Nitric oxide (NO) production by inducible NO synthase (iNOS) during inflammation is an essential element of antimicrobial immunity but can also contribute to host-induced tissue damage. Under conditions of bacterial sepsis, large amounts of NO are produced, causing hypotension, a critical pathological feature of septic shock. In sepsis caused by gram-positive organisms, the bacterial factors contributing to host NO production are poorly characterized. We show that a soluble toxin of Streptococcus pneumoniae, pneumolysin (Pln), is a key component initiating NO production from macrophages. In contrast to wild-type bacteria, a mutant of S. pneumoniae lacking Pln failed to elicit NO production from murine macrophages. Purified recombinant Pln induced NO production at low concentrations and independently of exogenous gamma interferon (IFN-gamma) priming of RAW 264.7 macrophages. However, IFN-gamma was essential for Pln-induced NO production, since primary macrophages from mice lacking the IFN-gamma receptor or interferon regulatory factor 1, a transcription factor essential for iNOS expression, failed to produce NO when stimulated with Pln. In addition, Pln acts as an agonist of tumor necrosis factor alpha and interleukin 6 production in macrophages. The properties of Pln, previously identified as a pore-forming hemolysin, also include a role as a general inflammatory agonist.

Animals↗

PubMed2005

Nature of a paramyxovirus replication promoter influences a nearby transcription signal.

The genomic and antigenomic 3' ends of the Sendai virus replication promoters are bi-partite in nature. They are symmetrically composed of leader or trailer sequences, a gene start (gs) or gene end (ge) site, respectively, and a simple hexameric repeat. Studies of how mRNA synthesis initiates from the first gene start site (gs1) have been hampered by the fact that gs1 is located between two essential elements of the replication promoter. Transcription initiation, then, is separated from the replication initiation site by only 56 nt on the genome, so that transcription and replication may sterically interfere with each other. In order to study the initiation of Sendai virus mRNAs without this possible interference, Sendai virus mini-genomes were prepared having tandem promoters in which replication takes place from the external one, whereas mRNA synthesis occurs from the internal one. Transcription now initiates at position 146 rather than position 56 relative to the genome 3' end. Under these conditions, it was found that the frequency with which mRNA synthesis initiates depends, in an inverse fashion, on the strength of the external replication promoter. It was also found that the sequences essential for replication are not required for basic mRNA synthesis as long as there is an external replication promoter at which viral RNA polymerase can enter the nucleocapsid template. The manner in which transcription and replication initiations influence each other is discussed.

3' Untranslated Regions↗

PubMed1986

Boron and calcium sites involved in indole-3-acetic Acid transport in sunflower hypocotyl segments.

Sunflower (Helianthus annuus L. cv Russian Mammoth) hypocotyl segments deficient in either B or Ca exhibited a higher rate of potassium leakage, compared to nondeficient segments. Potassium leakage, used here as an indication of membrane integrity, was completely reversed by the addition of H(3)BO(3) or Ca(NO(3))(2) to the incubation medium of the B-deficient or Ca-deficient hypocotyl segments, respectively. This role of B and Ca in membrane integrity, which may be important in the entry and exit of auxin in cells, is identified as the first site of action for each of these two essential elements in the basipetal secretion of auxin. A second site for B is postulated because auxin transport was not restored, even when K(+) leakage has been completely reversed to the nondeficient level, when B-deficient hypocotyls were incubated in B solution. This lack of reversibility of auxin transport implied that the incubation for 2 h in B solution was not enough to restore the auxin transport process. However, since the transfer of B-deficient seedlings to B solutions prevented further deterioration of auxin transport, these observations suggest that: (a) either an intact seedling, or a longer period of incubation of the hypocotyl in B solution, is required for the synthesis or maintenance of the functional second site for B; (b) B is probably essential in the synthesis of a ligand, which may or may not be needed to bind B, but which is essential in the basipetal transport of auxin. The second site for Ca in auxin transport, is indicated by the complete reversal of its inhibition in Ca-deficient hypocotyl, when incubated in Ca solution. The second site for Ca is thought to be directly involved in the secretion of auxin, in which Ca probably plays the role of a second messenger, as in stimulus-response coupling. The two sites for Ca can be distinguished from each other by their cation specificity. The requirement for Ca in the first site can be substituted by other divalent cations, while the second site is highly specific for Ca.

Journal Article↗

PubMed1991

Complex regulation of transcription from the hepatitis B virus major surface antigen promoter in human hepatoma cell lines.

A detailed mutational analysis of the regulatory DNA sequence elements that control expression of the hepatitis B virus major surface antigen gene was performed in the human hepatoma cell lines HepG2.1 and Huh7, using transient transfection assays. Seven regions (A to G) of the major surface antigen promoter located within 200 nucleotides of the RNA initiation site have been identified which influence the level of transcription from this promoter. The three distal regions (A to C), located between -188 and -68, appear to possess a level of redundancy in their ability to influence the transcriptional activity from the major surface antigen promoter. The simultaneous deletion of regions A, B, and C resulted in an approximately fourfold reduction in transcription from the major surface antigen promoter. Region D, located between -67 and -49, is an essential element of the major surface antigen promoter. The three proximal regions (E to G) are located within 45 nucleotides of the major transcription initiation site. Region E prevents the negative influence of region F and can compensate for the effect of mutation of region G on transcription from the major surface antigen promoter. Region G can compensate for the effect of the loss of a functional region E sequence on the transcriptional activity of the major surface antigen promoter only in the absence of a functional region F sequence. These results imply that the level of expression of the major surface antigen gene is controlled by the complex interplay between a minimum of six transcription factors which activate and one transcription factor which represses transcription from this gene.

Base Sequence↗

PubMed1988

Innervation of periodontal ligament and dental pulp in the rat incisor: an immunohistochemical investigation of neurofilament protein and glia-specific S-100 protein.

Nervous elements in the periodontal ligament and dental pulp of rat incisors were investigated by means of immunohistochemistry for neurofilament protein (NFP) and glia-specific S-100 protein. The periodontal ligament in the incisors was densely innervated by NFP-immunoreactive nerve fibers; the distribution of the nerve fibers and their terminations differed markedly from those in molars. NFP-positive, thick nerve bundles entered the lingual periodontal ligament through slits located in the mid-region of the alveolar socket, and immediately formed numerous Ruffini-like corpuscles. In the labial periodontal ligament, all of the NFP-immunoreactive nerve fibers terminated in free endings. The restricted location of the stretch receptor, Ruffini-like corpuscle, in the lingual periodontal ligament appears to be an essential element, because this region is regularly extended during mastication. The nervous elements were restricted to the alveolar half of the periodontal ligament in every region; they avoided the dental half of the periodontal ligament, which presumably moves continuously with the tooth. Pulpal nerve fibers in incisors also showed a characteristic distribution different from those in molars; individual nerve fibers with beaded structures ran in the center of the pulp toward the incisal edge, and did not form the subodontoblastic nerve plexus of Raschkow. Immunostaining for S-100 protein revealed a distribution pattern of nervous elements similar to that for NFP, suggesting that the nerves supplying the periodontal ligament and dental pulp were mostly covered by a Schwann sheath.

Animals↗

PubMedDate not supplied

Communication and end-of-life care in the intensive care unit: patient, family, and clinician outcomes.

Even though good communication among clinicians, patients, and family members is identified as the most important factor in end-of-life care in ICUs, it is the least accomplished. According to accumulated evidence, communication about end-of-life decisions in ICUs is difficult and flawed. Poor communication leaves clinicians and family members stressed and dissatisfied, as well as patients' wishes neglected. Conflict and anger both among clinicians and between clinicians and family members also result. Physicians and nurses lack communication skills, an essential element to achieve better outcomes at end of life. There is an emerging evidence base that proactive, multidisciplinary strategies such as formal and informal family meetings, daily team consensus procedures, palliative care team case finding, and ethics consultation improve communication about end-of-life decisions. Evidence suggests that improving end-of-life communication in ICUs can improve the quality of care by resulting in earlier transition to palliative care for patients who ultimately do not survive and by increasing family and clinician satisfaction. Both larger, randomized controlled trials and mixed methods designs are needed in future work. In addition, research to improve clinician communication skills and to assess the effects of organizational and unit context and culture on end-of-life outcomes is essential.

Communication↗

PubMed1999

Manganese scavenges superoxide and hydroxyl radicals: an in vitro study in rats.

The present study was designed to investigate the role of manganese (Mn) as an antioxidant element. In vitro experiments have been conducted to evaluate the ability of Mn in scavenging oxygen free radicals. Superoxide (O*-) and hydroxyl (OH*-) radicals were generated in vitro by using xanthine and xanthine oxidase system and fenton reactions respectively. Different concentrations of Mn (II) and Mn (III) were used in the reaction mixture to evaluate free radical scavenging ability of Mn. The results indicated that Mn scavenged superoxide radicals at nanomolar concentrations whereas hydroxyl radicals were scavenged at micromolar concentrations. In addition, Mn-superoxide dismutase (SOD) activity was measured in different regions of brain in adult male rats treated with MnCl2. The results showed that Mn-SOD activity increased in Mn treated animals. Therefore, the data support the hypothesis that Mn is one of the essential elements which can protect against oxidative damage, however, at higher concentrations Mn can be neurotoxic by generating the free radicals.

Animals↗

PubMed2005

The spectrin-associated cytoskeleton in mammalian heart.

The membrane-associated cytoskeleton of the cardiac muscle cell is emerging as an important element in the maintenance of normal cell functioning. Recently it was shown that when proteins (betaII-spectrin, muscle Lim-only protein, ankyrin-B, ankyrin-G) of this system are defective or deficient, cardiac malfunction ensues. It is well-established that the spectrin cytoskeleton is associated with the plasma membrane, but it was only lately demonstrated that its components also lie on internal cell membranes. This is particularly apparent in muscle cells of the heart which contain specialised intracellular membrane compartments particular to this cell type such as the sarcoplasmic reticulum and T-tubules. Cardiomyocytes are subjected to constant mechanical stress. Since their mechanics are controlled through coordination of calcium fluxes mediated via cell membrane-based assemblies, it is imperative that these essential elements withstand the displacement forces of contraction. Cardiomyocyte spectrin locates the multifunctional spectrin/actin-binding and membrane-binding component, protein 4.1, and they act together on the plasma membrane as well as on internal membranes. We have found that cardiac protein 4.1 links to the calcium handling apparatus whilst spectrins connect with the sarcomeric contractile elements of the cell. Overall this assembly fulfils roles in stabilising cardiomyocyte cell membranes and in coordinating the macromolecular protein accumulations which regulate and accomplish cardiac molecular crosstalk, whilst at the same time enabling the muscle cells to resist extreme forces of contraction.

Animals↗