Biomedical subjects

P Rouet

Publications and source records attributed to P Rouet.

At least 19 recordsLinked to original sources

PubMed2007

NMR and cDNA array analysis prior to heart failure reveals an increase of unsaturated lipids, a glutamine/glutamate ratio decrease and a specific transcriptome adaptation in obese rat heart.

Obesity is a risk factor for heart failure through a set of hemodynamic and hormonal adaptations, but its contribution at the molecular level is not clearly known. Therefore, we investigated the kinetic cardiac transcriptome and metabolome in the Spontaneous Hypertensive Heart Failure (SHHF) rat. The SHHF rat is devoid of leptin signaling when homozygous for a mutation of the leptin receptor (ObR) gene. The ObR-/- SHHF rat is obese at 4 months of age and prone to heart failure after 14 months whereas its lean counterpart ObR-/+ is prone to heart failure after 16 months. We used a set of rat pangenomic high-density macroarrays to monitor left ventricle cardiac transcriptome regulation in 4- and 10-month-old, lean and obese animals. Comparative analysis of left ventricle of 4- and 10-month-old lean rat revealed 222 differentially expressed genes while 4- and 10-month-old obese rats showed 293 differentially expressed genes. (1)H NMR analysis of the metabolome of left ventricular extracts displayed a global decrease of metabolites, except for taurine, and lipid concentration. This may be attributed to gene expression regulation and likely increased extracellular mass. The glutamine to glutamate ratio was significantly lower in the obese group. The relative unsaturation of lipids increased in the obese heart; in particular, omega-3 lipid concentration was higher in the 10-month-old obese heart. Overall, several specific kinetic molecular patterns act as a prelude to heart failure in the leptin signaling deficient SHHF obese rat.

Adaptation, Biological↗

PubMed2005

Insulin downregulates M(2)-muscarinic receptors in adult rat atrial cardiomyocytes: a link between obesity and cardiovascular complications.

OBJECTIVE: To determine whether decreased cardiac parasympathetic activity observed in obesity is due to insulin-induced alterations in cardiac M(2)-muscarinic receptors and/or adenylyl cyclase activity. DESIGN AND METHODS: After incubation with increasing concentrations of insulin, adult rat atrial cardiomyocytes were assayed for M(2)-muscarinic receptor binding density and affinity, and for M(2)R mRNA expression using RT-PCR analysis. Forskolin-stimulated adenylyl cyclase activity and its inhibition by carbachol were also assayed, as was endothelial nitric oxide synthase mRNA expression. The effects of insulin on M(2)-muscarinic receptor density and mRNA expression levels were analyzed using the insulin signaling inhibitors rapamycin, wortmanin and PD 098059. RESULTS: Insulin induces a concentration- and time-dependent decrease in expression of the M(2)R mRNA, and in [(3)H]N-methylscopolamine binding by the receptor. These effects on the M(2)R mRNA levels and on [(3)H]N-methylscopolamine binding were prevented by PD 98059, but not by wortmanin or rapamycin. Basal and forskolin-induced cAMP production did not differ, but the inhibition of forskolin-simulated enzyme activity by carbachol was blunted by insulin. No change in the mRNA levels for endothelial nitric oxide synthase was observed. CONCLUSION: In rat atrial cardiomyocytes, insulin markedly alters both the M(2)-muscarinic receptor density, and its mRNA expression through transcriptional regulation and adenylyl cyclase activity. These data suggest that the obesity-associated decrease in cardiac parasympathetic tone may be related to hyperinsulinemia, which could directly contribute to cardiovascular morbidity in obese patients.

Adenylyl Cyclases↗

PubMed2003

Characterization of semicarbazide-sensitive amine oxidase in human subcutaneous adipocytes and search for novel functions.

Numerous studies have characterized semicarbazide-sensitive amine oxidase activity (SSAO) in rat fat cells but this oxidase is scarcely documented in human adipose tissue. Our aim was to further characterize SSAO in human adipose tissue (activity, mRNA and protein abundance) and to investigate whether SSAO activity can interplay with glucose and lipid metabolism in human adipocytes via the hydrogen peroxide it generates. Polyclonal antibodies directed against bovine lung SSAO allowed the detection of a substantial amount of immunoreactive protein (apparent molecular mass 100 kDa) in human subcutaneous adipocytes from either mammary or abdominal fat depots. A 4-kb mRNA was detected in fat depots using a cDNA probe designed from the placenta SSAO sequence. Almost all the oxidation of benzylamine found in adipose tissue homogenates was due to fat cells and was located in the adipocyte membrane fraction. The oxidation of benzylamine and methylamine were similar and totally inhibited by semicarbazide or hydralazine but resistant to pargyline. Histamine was poorly oxidized. Benzylamine and methylamine dose-dependently stimulated glucose transport in intact adipocytes. This insulin-like effect of amines did not increase in the presence of 0.1 mM vanadate but was inhibited by semicarbazide and antioxidants. Benzylamine and methylamine also exhibited antilipolytic effects, with complete inhibition of lipolysis at 1 mM. These results show that fat cells from non-obese subjects express a membrane-bound SSAO which readily oxidizes exogenous amines, generates hydrogen peroxide and exerts short-term insulin-like actions on glucose and lipid metabolism.

Journal Article↗

PubMed2001

Semicarbazide-sensitive amine oxidase substrates stimulate glucose transport and inhibit lipolysis in human adipocytes.

Semicarbazide-sensitive amine oxidases (SSAO) are widely distributed enzymes scavenging biogenic or exogenous amines and generating hydrogen peroxide. We asked whether human adipose tissue could express SSAO. Since hydrogen peroxide exhibits pharmacological insulin-like effects, we also tested whether its endogenous production by SSAO could mimic several insulin effects on adipocytes, such as stimulation of glucose uptake and inhibition of lipolysis. The benzylamine oxidation by human adipose tissue was inhibited by semicarbazide or hydralazine and resistant to pargyline or selegiline. It was due to an SSAO activity localized in adipocyte membranes. A protein of 100-kDa and a 4-kb mRNA corresponding to SSAO were identified in either mammary or abdominal subcutaneous fat depots. In isolated adipocytes, SSAO oxidized similarly benzylamine and methylamine that dose dependently stimulated glucose transport in a semicarbazide-sensitive manner. Antioxidants also inhibited the benzylamine and methylamine effects. Moreover, the ability of diverse substrates to be oxidized by adipocytes was correlated to their effect on glucose transport. Benzylamine and methylamine exerted antilipolytic effects with a maximum attained at 1 mM. These results show that human adipocytes express a membrane-bound SSAO that not only readily oxidizes exogenous amines and generates H(2)O(2), but that also interplays with glucose and lipid metabolism by exerting insulin-like actions. Based on these results and the fact that variations in plasma levels of the soluble form of SSAO have been previously reported in diabetes, we propose that determination of adipocyte SSAO, feasible on subcutaneous microbiopsies, could bring relevant information in pathologies such as obesity or diabetes.

Adipocytes↗

PubMed1999

The alpha1-microglobulin/bikunin gene: characterization in mouse and evolution.

The 129Sv mouse gene coding for the alpha1-microglobulin/bikunin precursor has been isolated and characterized. The 11kb long gene contains ten exons, including six 5'-exons coding for alpha1-microglobulin and four 3'-exons encoding bikunin. Exon 7 also codes for the tribasic tetrapeptide RARR which connects the alpha1-microglobulin and bikunin parts. The sixth intron, which separates the alpha1-microglobulin and bikunin encoding parts, was compared in the human, mouse and a fish (plaice) gene. The size of this intron varies considerably, 6.5, 3.3 and 0.1kb in man, mouse and plaice, respectively. In all three genes, this intron contains A/T-rich regions, and retroposon elements are found in the first two genes. This indicates that this sixth intron is an unstable region and a hotspot for recombinational events, supporting the concept that the alpha1-microglobulin and bikunin parts of this gene are assembled from two ancestral genes. Finally, the nonsynonymous nucleotide substitution rate of the gene was determined by comparing coding sequences from ten vertebrate species. The results indicate that the alpha1-microglobulin part of the gene has evolved faster than the bikunin part.

Animals↗

PubMed1999

Testis expression of hormone-sensitive lipase is conferred by a specific promoter that contains four regions binding testicular nuclear proteins.

The testicular isoform of hormone-sensitive lipase (HSLtes) is encoded by a testis-specific exon and 9 exons common to the testis and adipocyte isoforms. In mouse, HSLtes mRNA appeared during spermiogenesis in round spermatids. Two constructs containing 1.4 and 0.5 kilobase pairs (kb) of the human HSLtes gene 5'-flanking region cloned upstream of the chloramphenicol acetyltransferase gene were microinjected into mouse oocytes. Analyses of enzyme activity in male and female transgenic mice showed that 0.5 kb of the HSLtes promoter was sufficient to direct expression only in testis. Cell transfection experiments showed that CREMtau, a testis-specific transcriptional activator, does not transactivate the HSLtes promoter. Using gel retardation assays, four testis-specific binding regions (TSBR) were identified using testis and liver nuclear extracts. The testis-specific protein binding on TSBR4 was selectively competed by a probe containing a SRY/Sox protein DNA recognition site. Sox5 and Sox6 which are expressed in post-meiotic germ cells bound TSBR4. Mutation of the AACAAAG motif in TSBR4 abolished the binding. Moreover, binding of the high mobility group domain of Sox5 induced a bend within TSBR4. Together, our results showed that 0.5 kb of the human HSLtes promoter bind Sox proteins and contain cis-acting elements essential for the testis specificity of HSL.

Animals↗

PubMed1999

Matrix metalloproteinase gelatinases in sulfur mustard-induced acute airway injury in guinea pigs.

Respiratory tract lesions induced by sulfur mustard (SM), a chemical warfare agent, are characterized by epithelial damage associated with inflammatory cell infiltration. To test the potential role of matrix metalloproteinase gelatinases in these lesions, we evaluated gelatinase activity, albumin content, and total cell count in bronchoalveolar lavage fluid of guinea pigs 24 h after an intratracheal injection of 0.2 mg/kg of SM. The bronchial lavage and alveolar lavage fluids were analyzed separately. The increase in inflammatory cell content of the bronchial lavage fluid, mainly macrophages, observed in SM-intoxicated guinea pigs was accompanied by an increase in albumin and in 92-kDa gelatinase activity. There was a significant correlation between albumin content and 92-kDa gelatinase activity (r = 0.67) and between 92-kDa gelatinase and the number of macrophages. Immunohistochemistry performed on tracheal sections showed the presence of 92-kDa gelatinase at the site of intraepithelial cleavages. Zymography analysis of culture medium conditioned by guinea pig tracheal epithelial cells demonstrated that these cells produced in vitro 92-kDa gelatinase on stimulation. Culture of human bronchial epithelial cells obtained by the explant technique showed a marked increase in 92-kDa gelatinase after exposure to 5 x 10(-5) M SM that reinforced the relevance of our animal results to human exposure to SM. These results suggest that in SM respiratory intoxication, 92-kDa gelatinase of both inflammatory and epithelial cell origins could be involved in epithelial cell detachment.

Albumins↗

PubMed1998

An array of binding sites for hepatocyte nuclear factor 4 of high and low affinities modulates the liver-specific enhancer for the human alpha1-microglobulin/bikunin precursor.

Alpha1-Microglobulin and bikunin are two plasma glycoproteins encoded by a gene for alpha1-microglobulin/bikunin precursor (AMBP). The strict liver-specific transcription of the AMBP gene is controlled by an elaborate and remote enhancer made of six clustered boxes numbered 1 to 6 (core enhancer) that are binding sites for the hepatocyte-enriched nuclear factors HNF-1, HNF-4, HNF-3, HNF-1, HNF-3 and HNF-4 respectively. Three further boxes, 7 to 9, have now been found in the enhancer area in a position 5' of box 2, 5' of box 1 and 3' of box 6, respectively. Electrophoretic mobility-shift assays with nuclear extracts from the HepG2 hepatoma cell line demonstrated that boxes 7 and 8 are both functional HNF-4-binding sites of high and low affinity respectively, whereas no binding capacity of box 9 was detected by this method. Transfection of HepG2 and Chinese hamster ovary cells with chloramphenicol acetyltransferase constructs harbouring the core or extended AMBP enhancer with wild-type or mutated boxes and co-transfection with expression plasmids for a wild-type or defective HNF-4 identified box 7 as an essential element for the basal activity of this enhancer. The response of boxes 7 and 8 varies with the level of HNF-4 in cells. Box 9 exhibits a repressor activity that can be detected when box 8 is ablated. In vivo this corresponds to conditions of low box 8 occupancy when the intracellular level of HNF-4 is limited. These results reinforce the view that the AMBP enhancer is a quite elaborate and unusual example of a modular enhancer whose activity is fine-tuned by the level of cognate nuclear factors in the cell.

Alpha-Globulins↗

PubMed1998

Down-regulation of negative acute-phase response genes by hypotonic stress in HepG2 hepatoma cells.

An increased hepatocellular hydration state (HS) that can be induced by hypotonic stress or a high glutamine uptake modulates the transcription of given genes in liver. This could be important in the acute phase (AP) of a systemic inflammation where both HS and glutamine uptake transiently increase in liver. In HepG2 hepatoma cells cultured in conditions of hypotonic stress or a high extracellular glutamine availability, a specifically decreased expression of two human mRNAs, namely those of alphal-microglobulin/bikunin precursor (AMBP) and alpha2-HS-glycoprotein, that are also down-regulated in liver by AP, could be seen. A functional analysis of the AMBP promoter indicated that this hypotonic stress-induced down-regulation takes place at a transcriptional level. In these experiments, the mRNA level and transcription of the glyceraldehyde-3-phosphate dehydrogenase gene that are known to be unmodified in AP did not exhibit any change. Given that hypotonic stress also upregulates the transcription of a liver gene that is also upregulated in AP [Meisse et al. (1998) FEBS Lett. 422, 3463481, the AP-associated increase in hepatocellular HS now appears to participate in the transcriptional control of both sets of genes that are up- or down-regulated in AP.

Acute-Phase Reaction↗

PubMed1996

The inter-alpha-inhibitor family: from structure to regulation.

Inter-alpha-inhibitor (IalphaI) and related molecules, collectively referred to as the IalphaI family, are a group of plasma protease inhibitors. They display attractive features such as precursor polypeptides that give rise to mature chains with quite distinct fates and functions, and inter-chain glycosaminoglycan bonds within the various molecules. The discovery of an ever growing number of such molecules has raised pertinent questions about their pathophysiological functions. The knowledge of this family has long been structure-oriented, whereas the structure/function and structure/regulation relationships of the family members and their genes have been largely ignored. These relationships are now being elucidated in events such as gene transcription, precursor processing, changes in plasma protein levels in health and disease and binding capacities that involve hyaluronan as well as other plasma proteins as ligands. This review presents some recent progress made in these fields that paves the way for an understanding of the functions of IalphaI family members in vivo. Finally, given the wealth of heterogeneous, complicated and sometimes contradictory nomenclatures and acronyms currently in use for this family, a new, uniform, nomenclature is proposed for IalphaI family genes, precursor polypeptides and assembled proteins.

Alpha-Globulins↗

PubMed1995

Double-strand breaks at the target locus stimulate gene targeting in embryonic stem cells.

Double-strand breaks (DSBs) are recombinogenic lesions in chromosomal DNA in yeast, Drosophila and Caenorhabditis elegans. Recent studies in mammalian cells utilizing the I-Scel endonuclease have demonstrated that in some immortalized cell lines DSBs in chromosomal DNA are also recombinogenic. We have now tested embryonic stem (ES) cells, a non-transformed mouse cell line frequently used in gene targeting studies. We find that a DSB introduced by I-Scel stimulates gene targeting at a selectable neo locus at least 50-fold. The enhanced level of targeting is achieved by transient expression of the I-Scel endonuclease. In 97% of targeted clones a single base pair polymorphism in the transfected homologous fragment was incorporated into the target locus. Analysis of the targeted locus demonstrated that most of the homologous recombination events were 'two-sided', in contrast to previous studies in 3T3 cells in which 'one-sided' homologous events predominated. Thus ES cells may be more faithful in incorporating homologous fragments into their genome than other cells in culture.

Animals↗

PubMed1995

Hierarchy and positive/negative interplays of the hepatocyte nuclear factors HNF-1, -3 and -4 in the liver-specific enhancer for the human alpha-1-microglobulin/bikunin precursor.

Alpha-1-microglobulin and bikunin are two plasma glycoproteins encoded by an alpha-1-microglobulin/bikunin precursor (AMBP) gene. The strict liver-specific expression of the AMBP gene is controlled by a potent enhancer made of six clustered boxes numbered 1-6 that have been reported to be proven or potential binding sites for the hepatocyte-enriched nuclear factors HNF-1, -4, -3, -1, -3, -4, respectively. In the present study, electromobility shift assays of wild-type or mutated probes demonstrated that the boxes 1-5 have a binding capacity for their cognate HNF protein. Box 5 is also a target for another, as yet unidentified, factor. A functional analysis of the wild-type or mutated enhancer, driving its homologous promoter and a reporter CAT gene in the HepG2 hepatoma cell line, demonstrated that all six boxes participate in the enhancer activity, with the primary influence of box 4 (HNF-1) and box 2 (HNF-4). A similar analysis in the HNF-free CHO cell line co-transfected with one or several HNF factors further demonstrated various interplays between boxes: box 3 (HNF-3 alpha and beta) has a negative influence over the major HNF-4 box 2 as well as a positive influence over the major HNF-1 box 4.

Alpha-Globulins↗

PubMed1994

Expression of a site-specific endonuclease stimulates homologous recombination in mammalian cells.

Double-strand breaks introduced into DNA in vivo have been shown to enhance homologous recombination in a variety of chromosomal and extrachromosomal loci in Saccharomyces cerevisiae. To introduce double-strand breaks in DNA at defined locations in mammalian cells, we have constructed a mammalian expression vector for a modified form of I-Sce I, a yeast mitochondrial intron-encoded endonuclease with an 18-bp recognition sequence. Expression of the modified I-Sce I endonuclease in COS1 cells results in cleavage of model recombination substrates and enhanced extrachromosomal recombination, as assayed by chloramphenicol acetyltransferase activity and Southern blot analysis. Constitutive expression of the endonuclease in mouse 3T3 cells is not lethal, possibly due to either the lack of I-Sce I sites in the genome or sufficient repair of them. Expression of an endonuclease with such a long recognition sequence will provide a powerful approach to studying a number of molecular processes in mammalian cells, including homologous recombination.

3T3 Cells↗

PubMed1994

Introduction of double-strand breaks into the genome of mouse cells by expression of a rare-cutting endonuclease.

To maintain genomic integrity, double-strand breaks (DSBs) in chromosomal DNA must be repaired. In mammalian systems, the analysis of the repair of chromosomal DSBs has been limited by the inability to introduce well-defined DSBs in genomic DNA. In this study, we created specific DSBs in mouse chromosomes for the first time, using an expression system for a rare-cutting endonuclease, I-SceI. A genetic assay has been devised to monitor the repair of DSBs, whereby cleavage sites for I-SceI have been integrated into the mouse genome in two tandem neomycin phosphotransferase genes. We find that cleavage of the I-SceI sites is very efficient, with at least 12% of stably transfected cells having at least one cleavage event and, of these, more than 70% have undergone cleavage at both I-SceI sites. Cleavage of both sites in a fraction of clones deletes 3.8 kb of intervening chromosomal sequences. We find that the DSBs are repaired by both homologous and nonhomologous mechanisms. Nonhomologous repair events frequently result in small deletions after rejoining of the two DNA ends. Some of these appear to occur by simple blunt-ended ligation, whereas several others may occur through annealing of short regions of terminal homology. The DSBs are apparently recombinogenic, stimulating gene targeting of a homologous fragment by more than 2 orders of magnitude. Whereas gene-targeted clones are nearly undetectable without endonuclease expression, they represent approximately 10% of cells transfected with the I-SceI expression vector. Gene targeted clones are of two major types, those that occur by two-sided homologous recombination with the homologous fragment and those that occur by one-sided homologous recombination. Our results are expected to impact a number of areas in the study of mammalian genome dynamics, including the analysis of the repair of DSBs and homologous recombination and, potentially, molecular genetic analyses of mammalian genomes.

3T3 Cells↗

PubMed1993

Human inter-alpha-inhibitor family in inflammation: simultaneous synthesis of positive and negative acute-phase proteins.

The inter-alpha-inhibitor (I alpha I) family encompasses four plasma proteins, namely free bikunin as well as I alpha I, pre-alpha-inhibitor (P alpha I) and inter-alpha-like inhibitor (I alpha LI). Each of the last three proteins is a distinct assembly of one bikunin chain with one or more unique heavy (H) chains designated H1, H2 and H3. The three H chains and the bikunin chain are encoded by four distinct mRNAs. These molecules and chains, as well as the corresponding mRNAs, were quantified in sera and liver biopsies from a series of patients with or without mild or severe acute infection. The decrease or increase observed for a given molecule or chain in the serum was in agreement with a similar change in the corresponding liver mRNA. In acute inflammation the H2 and bikunin chains are down-regulated and the relevant molecules (I alpha I, I alpha LI) behave as negative acute-phase proteins, whereas the H3 chain is up-regulated and the corresponding P alpha I molecule is a positive acute-phase protein. Also, P alpha I displays a higher-than-usual M(r); this is probably due to ligand binding. The H1 gene does not seem to be affected by the inflammatory condition. The quantitative changes in RNA levels seen in vivo were confirmed in vitro in the human hepatoma Hep3B cell line prior to or after induction with the acute-phase mediators interleukin-1 and/or -6. These results provide the first example in humans of positive and negative acute-phase proteins that are encoded by evolutionary related genes.

Acute-Phase Proteins↗

PubMed1992

A potent enhancer made of clustered liver-specific elements in the transcription control sequences of human alpha 1-microglobulin/bikunin gene.

alpha 1-Microglobulin (A1M) and bikunin are plasma proteins which are present both as free molecules and as complexes with either IgA heavy chains for A1M or the H1, H2, and H3 heavy chains of the inter-alpha-inhibitor family for bikunin. Mature A1M and bikunin originate from the cleavage of an A1M/bikunin precursor (ABP) synthesized from a single gene with liver-specific expression. Five kilobases of the 5'-flanking region of the human ABP gene were sequenced. Deletion mutants of this region subcloned upstream of a CAT reporter gene were transfected into HepG2 hepatoma cells. A segment covering the -2.7- to -2.8-kb area is required for full activity of the ABP gene. This segment contains a cluster of six elements (boxes 1-6, 5' to 3') which are potential binding sites for the liver-enriched trans-acting factors HNF-1, HNF-4, HNF-3, HNF-1, HNF-3, and HNF-4, respectively. This cluster enhances the activity of heterologous minimal promoters in a position- and distance-independent fashion in HepG2 cells. This enhancer activity is restricted to liver cells as the cluster is unable to activate promoters in Chinese hamster ovary (CHO) or HeLa cells. By band-shift experiments we have shown that the liver-enriched transcription factors HNF-1, or HNF-3, do bind to boxes 1 and 4, or 3, respectively. The combination of a weak promoter and a strong distant and liver-specific enhancer distinguishes the ABP gene from most other plasma protein genes expressed in hepatocytes.

Alpha-Globulins↗

PubMed1992

Homologous chromosomal locations of the four genes for inter-alpha-inhibitor and pre-alpha-inhibitor family in human and mouse: assignment of the ancestral gene for the lipocalin superfamily.

The inter-alpha-inhibitor (I alpha I) and pre-alpha-inhibitor (P alpha I) family is composed of three plasma protease inhibitors, I alpha I, P alpha I, and bikunin, whose chains are encoded by a set of three evolutionarily related heavy (H) chain genes designated H1, H2, and H3 and a fourth gene, the so-called alpha 1-microglobulin/bikunin precursor (AMBP) gene. The latter codes for a precursor that splits into: (i) alpha 1-microglobulin, which belongs to the lipocalin superfamily; and (ii) bikunin, which is made up of two tandemly arranged protease inhibitor domains and belongs to the superfamily of Kunitz-type protease inhibitors. The bikunin chain is found in I alpha I and P alpha I molecules and it is also present as a free molecule in plasma. In human, the AMBP and H2 genes have been mapped to 9q32-q34 and 10p14-p15, respectively, while the H1 and H3 genes are tandemly located at 3p21.1-p21.2. In situ hybridization mappings indicate that the mouse AMBP gene (Intin-4) is located at 4C1----C4, and the H1 (Intin-1) and H3 (Intin-3) genes are colocated at 14A2----C1. In interspecific backcrosses (C57BL/6Pas x Mus spretus) a TaqI restriction variant in (and/or near) the H2 (Intin-2) gene identified a linkage of this gene with other polymorphic loci, which assigns Intin-2 to the centromeric area of chromosome 2. All such assignments are in conserved chromosomal regions between human and mouse. Therefore the genetic events that gave rise to the four I alpha I family genes took place prior to the divergence between human and mouse.(ABSTRACT TRUNCATED AT 250 WORDS)

Alpha-Globulins↗

PubMed1992

Electrophoretic pattern of the inter-alpha-inhibitor family proteins in human serum, characterized by chain-specific antibodies.

The inter-alpha-inhibitor (I alpha I) family encompasses four plasma proteins, namely free bikunin as well as I alpha I, pre-alpha-inhibitor (P alpha I) and inter-alpha-like inhibitor (I alpha LI). Each of the last three proteins is a distinct assembly of one bikunin chain with one or two out of three distinct, heavy (H) chains designated H1, H2 and H3. I alpha I is made of [H1 + H2 + bikunin], P alpha I is made of [H3 + bikunin] and I alpha LI is made of [H2 + bikunin]. We characterized various I alpha I family-related antisera/antibodies, including a reagent recognizing bikunin, another directed against the four H1, H2, H3 and bikunin chains, and a third one directed against both H1 and H2 chains. By a simplified absorption procedure of the latter two antisera onto solid-phase immunoadsorbents made with i) purified I alpha I, or ii) a recombinant H1 polypeptide, we also obtained specific anti-H3 or anti-H2 antibodies, respectively. This series of new antibodies was used to identify each component within the pattern of bands corresponding to I alpha I family in human serum, as separated by SDS-PAGE and western blotting.

Alpha-Globulins↗