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F Hauser

Publications and source records attributed to F Hauser.

At least 19 recordsLinked to original sources
PubMed2005

Design and validation of a partial-genome microarray for transcriptional profiling of the Bradyrhizobium japonicum symbiotic gene region.

The design and use of a pilot microarray for transcriptome analysis of the symbiotic, nitrogen-fixing Bradyrhizobium japonicum is reported here. The custom-synthesized chip (Affymetrix GeneChip) features 738 genes, more than half of which belong to a 400-kb chromosomal segment strongly associated with symbiosis-related functions. RNA was isolated following an optimized protocol from wild-type cells grown aerobically and microaerobically, and from cells of aerobically grown regR mutant and microaerobically grown nifA mutant. Comparative microarray analyses thus revealed genes that are transcribed in either a RegR- or a NifA-dependent manner plus genes whose expression depends on the cellular oxygen status. Several genes were newly identified as members of the RegR and NifA regulons, beyond genes, which had been known from previous work. A comprehensive transcription analysis was performed with one of the new RegR-controlled genes (id880). Expression levels determined by microarray analysis of selected NifA- and RegR-controlled genes corresponded well with quantitative real-time PCR data, demonstrating the high complementarity of microarray analysis to classical methods of gene expression analysis in B. japonicum. Nevertheless, several previously established members of the NifA regulon were not detected as transcribed genes by microarray analysis, confirming the potential pitfalls of this approach also observed by other authors. By and large, this pilot study has paved the way towards the genome-wide transcriptome analysis of the 9.1-Mb B. japonicum genome.

Bacterial Proteins↗
PubMed2001

Cloning, expression, and characterization of tomato (Lycopersicon esculentum) aminopeptidase P.

A cDNA (LeAPP2) was cloned from tomato coding for a 654 amino acid protein of 72.7 kDa. The deduced amino acid sequence was >40% identical with that of mammalian aminopeptidase P, a metalloexopeptidase. All amino acids reported to be important for binding of the active site metals and catalytic activity, respectively, were conserved between LeAPP2 and its mammalian homologues. LeAPP2 was expressed in Escherichia coli in N-terminal fusion with glutathione S-transferase and was purified from bacterial extracts. LeAPP2 was verified as an aminopeptidase P, hydrolyzing the amino-terminal Xaa-Pro bonds of bradykinin and substance P. LeAPP2 also exhibited endoproteolytic activity cleaving, albeit at a reduced rate, the internal -Phe-Gly bond of substance P. Apparent K(m) (15.2 +/- 2.4 microm) and K(m)/k(cat) (0.94 +/- 0.11 mm(-1) x s(-1)) values were obtained for H-Lys(Abz)-Pro-Pro-pNA as the substrate. LeAPP2 activity was maximally stimulated by addition of 4 mm MnCl(2) and to some extent also by Mg(2+), Ca(2+), and Co(2+), whereas other divalent metal ions (Cu(2+), Zn(2+)) were inhibitory. Chelating agents and thiol-modifying reagents inhibited the enzyme. The data are consistent with LeAPP2 being a Mn(II)-dependent metalloprotease. This is the first characterization of a plant aminopeptidase P.

Amino Acid Sequence↗
PubMed2001

Hypocretin (orexin) in the rat pineal gland: a central transmitter with effects on noradrenaline-induced release of melatonin.

Hypocretin-1 (HCRT-1) and hypocretin 2 (HCRT-2), also known as orexin-A and orexin-B, are two neuropeptides derived from the same precursor. Hypocretinergic neurons have been found exclusively in the hypothalamic dorsolateral area. These neurons are implicated in sleep and feeding through activation of specific G-protein-coupled orexin-1 and orexin-2 receptor (OR-R1 and OR-R2). The purpose of this study was to determine the existence of the HCRT peptides in the central input of the rat pineal gland. Further, OR-R1 and OR-R2 expression was determined in the pineal gland and the effect of HCRT-2 on melatonin synthesis and secretion was analysed in dissociated rat pinealocytes. A large contingent of HCRT-positive nerve fibres and terminals were observed in the epithalamus, many of which entered into the pineal parenchyma. A significant number of nerve fibres endowed with positive boutons were identified in the pineal stalk, though the number of positive fibres decreased along the extension of the stalk. So far, no positive fibres have been found in the superficial pineal gland. RT-PCR analysis revealed the expression of OR-R2 mRNA, whereas OR-R1-receptor mRNA was not detected. When tested alone, HCRT-2 had no effect on secretion of melatonin from cultured rat pinealocytes. However, HCRT-2 partially inhibited (by a maximum of 30%) the beta-adrenergic-induced melatonin secretion. The same effect was seen on activation of N-acetyltransferase activity. The distribution and the large number of HCRT-positive fibres together with the effect on noradrenaline-mediated melatonin release through specific receptors suggests that these peptides may be significant central transmitters in pineal function, probably mediating homeostatic signals to the pineal gland.

Acetyltransferases↗
PubMed2000

Genomic organization and splicing variants of a peptidylglycine alpha-hydroxylating monooxygenase from sea anemones.

Cnidarians are primitive animals that use neuropeptides as their transmitters. All the numerous cnidarian neuropeptides isolated, so far, have a carboxy-terminal amide group that is essential for their actions. This strongly suggests that alpha-amidating enzymes are essential for the functioning of primitive nervous systems. In mammals, peptide amidation is catalyzed by two enzymes, peptidylglycine alpha-hydroxylating monooxygenase (PHM) and peptidyl-alpha-hydroxyglycine alpha-amidating lyase (PAL) that act sequentially. These two activities are contained within one bifunctional enzyme, peptidylglycine alpha-amidating monooxygenase (PAM), which is coded for by a single gene. In a previous paper (F. Hauser et al., Biochem. Biophys. Res. Commun. 241, 509-512, 1997) we have cloned the first known cnidarian PHM from the sea anemone Calliactis parasitica. In the present paper we have determined the structure of its gene (CP1). CP1 is >12 kb in size and contains 15 exons and 14 introns. The last coding exon (exon 15) contains a stop codon, leaving no room for PAL and, thereby, for a bifunctional PAM enzyme as in mammals. Furthermore, we found a CP1 splicing variant (CP1-B) that contains exon-9 instead of exon-8, which was present in the previously characterized PHM cDNA (CP1-A). CP1-A and -B have 97% amino acid sequence identity, whereas both splicing variants have around 42% sequence identity with the PHM part of rat PAM. Essential amino acid residues for the catalytic activity and the 3D structure of PHM are conserved between CP1-A, -B and the PHM part of rat PAM. Furthermore, eight introns in CP1 occur in the same positions and have the same intron phasing as eight introns in the rat PAM gene, showing that the sea anemone PHM is not only structurally, but also evolutionarily related to the PHM part of rat PAM.

Alternative Splicing↗
PubMed2000

Molecular cloning, genomic organization, developmental regulation, and a knock-out mutant of a novel leu-rich repeats-containing G protein-coupled receptor (DLGR-2) from Drosophila melanogaster.

After screening the Berkeley Drosophila Genome Project database with sequences from a recently characterized Leu-rich repeats-containing G protein-coupled receptor (LGR) from Drosophila (DLGR-1), we identified a second gene for a different LGR (DLGR-2) and cloned its cDNA. DLGR-2 is 1360 amino acid residues long and shows a striking structural homology with members of the glycoprotein hormone [thyroid-stimulating hormone (TSH); follicle-stimulating hormone (FSH); luteinizing hormone/choriogonadotropin (LH/CG)] receptor family from mammals and with two additional, recently identified mammalian orphan LGRs (LGR-4 and LGR-5). This homology includes the seven transmembrane region (e.g., 49% amino acid identity with the human TSH receptor) and the very large extracellular amino terminus. This amino terminus contains 18 Leu-rich repeats-in contrast with the 3 mammalian glycoprotein hormone receptors and DLGR-1 that contain 9 Leu-rich repeats, but resembling the mammalian LGR-4 and LGR-5 that each have 17 Leu-rich repeats in their amino termini. The DLGR-2 gene is >18.6 kb pairs long and contains 15 exons and 14 introns. Four intron positions coincide with the intron positions of the three mammalian glycoprotein hormone receptors and have the same intron phasing, showing that DLGR-2 is evolutionarily related to these mammalian receptors. The DLGR-2 gene is located at position 34E-F on the left arm of the second chromosome and is expressed in embryos and pupae but not in larvae and adult flies. Homozygous knock-out mutants, where the DLGR-2 gene is interrupted by a P element insertion, die around the time of hatching. This finding, together with the expression data, strongly suggests that DLGR-2 is exclusively involved in development.

Alternative Splicing↗
PubMed1999

Expression and developmental regulation of the Hydra-RFamide and Hydra-LWamide preprohormone genes in Hydra: evidence for transient phases of head formation.

Hydra magnipapillata has three distinct genes coding for preprohormones A, B, and C, each yielding a characteristic set of Hydra-RFamide (Arg-Phe-NH2) neuropeptides, and a fourth gene coding for a preprohormone that yields various Hydra-LWamide (Leu-Trp-NH2) neuropeptides. Using a whole-mount double-labeling in situ hybridization technique, we found that each of the four genes is specifically expressed in a different subset of neurons in the ectoderm of adult Hydra. The preprohormone A gene is expressed in neurons of the tentacles, hypostome (a region between tentacles and mouth opening), upper gastric region, and peduncle (an area just above the foot). The preprohormone B gene is exclusively expressed in neurons of the hypostome, whereas the preprohormone C gene is exclusively expressed in neurons of the tentacles. The Hydra-LWamide preprohormone gene is expressed in neurons located in all parts of Hydra with maxima in tentacles, hypostome, and basal disk (foot). Studies on animals regenerating a head showed that the prepro-Hydra-LWamide gene is expressed first, followed by the preprohormone A and subsequently the preprohormone C and the preprohormone B genes. This sequence of events could be explained by a model based on positional values in a morphogen gradient. Our head-regeneration experiments also give support for transient phases of head formation: first tentacle-specific preprohormone C neurons (frequently associated with a small tentacle bud) appear at the center of the regenerating tip, which they are then replaced by hypostome-specific preprohormone B neurons. Thus, the regenerating tip first attains a tentacle-like appearance and only later this tip develops into a hypostome. In a developing bud of Hydra, tentacle-specific preprohormone C neurons and hypostome-specific preprohormone B neurons appear about simultaneously in their correct positions, but during a later phase of head development, additional tentacle-specific preprohormone C neurons appear as a ring at the center of the hypostome and then disappear again. Nerve-free Hydra consisting of only epithelial cells do not express the preprohormone A, B, or C or the LWamide preprohormone genes. These animals, however, have a normal phenotype, showing that the preprohormone A, B, and C and the LWamide genes are not essential for the basic pattern formation of Hydra.

Animals↗
PubMed1999

Neuropeptide Y (NPY) and NPY receptors in the rat pineal gland.

NPY is considered to play an important role in pineal function, because it is co-stored with the dominant pineal transmitter noradrenaline. However, little evidence from the literature suggests that NPY alone is a strong regulator of melatonin synthesis or secretion and it is therefore more likely that NPY modulates noradrenergic neurotransmission in the rat pineal gland. The purpose of the present studies was to determine the nature and origin of NPYergic inputs to, and the type of specific NPY receptor subtypes in, the rat pineal gland. Gel filtration and immunocytochemistry using region-specific antisera revealed that all proNPY present in intrapineal nerve fibres is cleaved to amidated NPY and a C-terminal flanking peptide of NPY (CPON). The vast majority of NPY content in the pineal gland was found to be of sympathetic origin. Receptor autoradiography showed that only a few NPY specific binding sites were present in the superficial pineal gland. A reverse transcriptase polymerase chain reaction detected sequences of only NPY receptor subtype Y1 and not other NPY receptor subtypes in pineal extracts. These results together with the available literature imply that NPY under certain conditions is co-released with noradrenaline and exerts its actions either presynaptically or on the pinealocyte through a Y1 receptor. The available data indicate that NPY has no effect alone, but acts in concert with noradrenaline. A presynaptic action regulating noradrenaline neurotransmission is also possible. NPY has been reported only to act on melatonin secretion in vitro, and it remains to be established what function NPY plays in the pineal gland in vivo. This paper discuss possible modulatory actions of NPY being a predominant sympathetic transmitter.

Animals↗
PubMed1998

Genomic organization of a receptor from sea anemones, structurally and evolutionarily related to glycoprotein hormone receptors from mammals.

Cnidarians (e.g., sea anemones and corals) are the lowest animal group having a nervous system. Previously, we cloned a receptor from sea anemones that showed a strong structural similarity to the glycoprotein hormone (TSH, FSH, LH/CG) receptors from mammals. Here, we determine the genomic organization of this sea anemone receptor. The receptor gene contains eight introns that are all localized within a region coding for the large extracellular N terminus. These introns occur at the same positions and have the same intron phasing as eight introns in the genes coding for the mammalian glycoprotein hormone receptors, indicating that the cnidarian and mammalian receptor genes are evolutionarily related. As with the mammalian receptor genes, the sea anemone receptor gene does not contain introns in the region coding for the transmembrane and intracellular domains. Southern blot analyses show that the cnidarian receptor is coded for by a single gene.

Animals↗
PubMed1998

Molecular cloning, genomic organization and developmental regulation of a novel receptor from Drosophila melanogaster structurally related to gonadotropin-releasing hormone receptors for vertebrates.

After screening the data base of the Berkeley Drosophila Genome Project with a sequence coding for the transmembrane region of a G protein-coupled receptor, we found that Drosophila might contain a gene coding for a receptor that is structurally related to the Gonadotropin-Releasing Hormone (GnRH) receptors from vertebrates. Using the polymerase chain reaction, with Drosophila cDNA as a template, and oligonucleotide probes coding for the presumed exons of this gene, we were able to clone the cDNA coding for this receptor. The transmembrane region of the receptor shows 36% amino acid residue identity with the transmembrane region of the catfish and 31% amino acid residue identity with that of the rat GnRH receptor. The Drosophila receptor gene contains six introns, whereas the rat gene contains two: one intron in the Drosophila gene occurs at exactly the same position and has the same intron phasing as one intron in the rat gene, suggesting that the Drosophila and mammalian GnRH receptor genes are evolutionarily related. Northern blot analyses show that the Drosophila receptor gene is progressively expressed during larval development with a prominent maximum at the 3rd instar larval stage. Pupae contain low amounts of receptor mRNA, while adult flies contain higher levels, with males having about five times more receptor mRNA than females flies. Southern blot analyses show that Drosophila contains only one copy of the receptor gene, which is located at position 27A2-B1 of chromosome 2. This paper is the first report on the molecular cloning of a member of the GnRH receptor family from invertebrates.

Amino Acid Sequence↗
PubMed1998

Three different prohormones yield a variety of Hydra-RFamide (Arg-Phe-NH2) neuropeptides in Hydra magnipapillata.

The freshwater polyp Hydra is the most frequently used model for the study of development in cnidarians. Recently we isolated four novel Arg-Phe-NH2 (RFamide) neuropeptides, the Hydra-RFamides I-IV, from Hydra magnipapillata. Here we describe the molecular cloning of three different preprohormones from H. magnipapillata, each of which gives rise to a variety of RFamide neuropeptides. Preprohormone A contains one copy of unprocessed Hydra-RFamide I (QWLGGRFG), II (QWFNGRFG), III/IV [(KP)HLRGRFG] and two putative neuropeptide sequences (QLMSGRFG and QLMRGRFG). Preprohormone B has the same general organization as preprohormone A, but instead of unprocessed Hydra-RFamide III/IV it contains a slightly different neuropeptide sequence [(KP)HYRGRFG]. Preprohormone C contains one copy of unprocessed Hydra-RFamide I and seven additional putative neuropeptide sequences (with the common N-terminal sequence QWF/LSGRFGL). The two Hydra-RFamide II copies (in preprohormones A and B) are preceded by Thr residues, and the single Hydra-RFamide III/IV copy (in preprohormone A) is preceded by an Asn residue, confirming that cnidarians use unconventional processing signals to generate neuropeptides from their precursor proteins. Southern blot analyses suggest that preprohormones A and B are each coded for by a single gene, whereas one or possibly two closely related genes code for preprohormone C. Northern blot analyses and in situ hybridizations show that the gene coding for preprohormone A is expressed in neurons of both the head and foot regions of Hydra, whereas the genes coding for preprohormones B and C are specifically expressed in neurons of different regions of the head. All of this shows that neuropeptide biosynthesis in the primitive metazoan Hydra is already rather complex.

Amino Acid Sequence↗
PubMed1997

Molecular cloning of a peptidylglycine alpha-hydroxylating monooxygenase from sea anemones.

Cnidarians are the lowest animal group having a nervous system. The primitive nervous systems of cnidarians produce large amounts of a variety of neuropeptides, of which many or perhaps all are amidated at their C terminus. In vertebrates, peptide amidation is catalyzed by two enzymes acting sequentially, peptidyl-glycine alpha-hydroxylating monooxygenase (PHM) and peptidyl-alpha-hydroxyglycine alpha-amidating lyase (PAL). In mammals both enzymatic activities are contained within a bifunctional protein that is coded for by a single gene. Using PCR and degenerated oligonucleotides derived from conserved regions of PHM, we have now cloned a PHM from the sea anemone Calliactis parasitica showing 42% amino acid sequence identity with rat PHM. Among the conserved (identical) amino acid residues are five histidine and one methionine residue, which bind two Cu2+ atoms that are essential for PHM activity. No cDNA coding for PAL could be identified, suggesting that sea anemone PAL is coded for by a gene that is different from the sea anemone PHM gene, a situation similar to the one found in insects. This is the first report on the molecular cloning of a cnidarian PHM.

Amino Acid Sequence↗
PubMed1997

Molecular cloning, genomic organization, and developmental regulation of a novel receptor from Drosophila melanogaster structurally related to members of the thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone/choriogonadotropin receptor family from mammals.

Using oligonucleotide probes derived from consensus sequences for glycoprotein hormone receptors, we have cloned an 831-amino acid residue-long receptor from Drosophila melanogaster that shows a striking structural homology with members of the glycoprotein hormone (thyroid-stimulating hormone (TSH); follicle-stimulating hormone (FSH); luteinizing hormone/choriogonadotropin (LH/CG)) receptor family from mammals. This homology includes a very large, extracellular N terminus (20% sequence identity with rat TSH, 19% with rat FSH, and 20% with the rat LH/CG receptor) and a seven-transmembrane region (53% sequence identity with rat TSH, 50% with rat FSH, and 52% with the rat LH/CG receptor). The Drosophila receptor gene is >7.5 kilobase pairs long and contains 17 exons and 16 introns. Seven intron positions coincide with introns in the mammalian glycoprotein hormone receptor genes and have the same intron phasing. This indicates that the Drosophila receptor is evolutionarily related to the mammalian receptors. The Drosophila receptor gene is located at position 90C on the right arm of the third chromosome. The receptor is strongly expressed starting 8-16 h after oviposition, and the expression stays high until after pupation. Adult male flies express high levels of receptor mRNA, but female flies express about 6 times less. The expression pattern in embryos and larvae suggests that the receptor is involved in insect development. This is the first report on the molecular cloning of a glycoprotein hormone receptor family member from insects.

Amino Acid Sequence↗
PubMed1997

Intestinal trefoil factor (TFF 3) and pS2 (TFF 1), but not spasmolytic polypeptide (TFF 2) mRNAs are co-expressed in normal, hyperplastic, and neoplastic human breast epithelium.

pS2-TFF 1 is expressed in breast cancers and has been investigated as a potential prognostic factor reflecting oestrogen dependence. The relationship to the expression of other trefoil peptides, human spasmolytic polypeptide (hSP-TFF 2) and intestinal trefoil factor (hITF/hPI.B-TFF 3) is documented here. Fifty-seven breast specimens were selected from surgical pathology archives and included five normal breasts (two lactating), seven benign proliferative lesions, 11 ductal carcinomas in situ (DCIS), three lobular carcinomas in situ (LCIS), 24 invasive ductal carcinomas (IDC), and seven invasive lobular carcinomas (ILC). The comparative distribution of trefoil mRNAs was assessed by in situ hybridization using 35S-labelled riboprobes and immunohistochemical staining for pS2-TFF 1 and hSP-TFF 2. pS2-TFF 1 and hITF/hPI.B-TFF 3 mRNA were focally present at low signal intensity in normal and benign breast. Both pS2-TFF 1 and hITF/hPI.B-TFF 3 were expressed in all DCIS, LCIS and ILC, and 21/24 IDC. Overall, expression patterns of pS2-TFF 1 and hITF/hPI.B-TFF 3 coincided, but hITF/hPI.B-TFF 3 mRNA was usually found in a greater proportion of cells. Expression of hSP-TFF 2 peptide or mRNA was not detected in any of these cases. MCF 7 breast carcinoma cells also expressed hITF/hPI.B-TFF 3 and pS2-TFF 1 mRNAs but not hSP-TFF 2. hITF/hPI.B-TFF 3 co-expression with pS2-TFF 1 may act as a prognostic factor, but also raises questions about the regulatory pathway for pS2-TFF 1 hITF/hPI.B-TFF 3. Trefoil factors have effects on cell motility and spreading in vitro, and co-expression of hITF/hPI.B-TFF 3 with pS2-TFF 1 could be functionally significant if they form a heterodimer or compete for receptor binding. Absence of hSP-TFF 2 expression may be of equal relevance to tumour cell biology.

Blotting, Northern↗
PubMed1994

Sequence analysis of the promoter region of the rat somatostatin receptor subtype 1 gene.

Somatostatin receptor (SSTR) subtype genes are differentially expressed in brain and various peripheral tissues. RNA blotting and semiquantitative PCR analyses have revealed low levels of SSTR1 mRNA in the gastrointestinal tract and relatively high levels in GH3 anterior pituitary cells. As a first step in the investigation of the regulation of SSTR1 gene expression, we isolated a genomic fragment that contains the promoter region and determined the transcriptional initiation site. The SSTR1 gene lacks introns and TATA and CAAT motifs, but possesses several consensus recognition sequences for the transcription factors GCF and AP-2. The presence, also, of two Pit-1 binding sites could explain the high SSTR1 mRNA levels in GH3 cells.

Animals↗
PubMed1994

Molecular anatomy of a skin gland: histochemical and biochemical investigations on the mucous glands of Xenopus laevis.

The purpose of this study was to investigate the structure and chemical composition of the mucous skin gland of Xenopus laevis by combined morphological and biochemical techniques. Protein backbones of mucins were localized immunohistochemically in the gland with anti-peptide antibodies. Acid mucins were demonstrated by conventional histochemical techniques and their terminal carbohydrate residues were localized by lectin histochemistry. A close correlation between antibody and lectin binding of the same glycoproteins was achieved on Western blots from isolated skin gland mucins, indicating that the lectin-binding sites were due to defined mucin molecules. The cone cell, thought to be a degenerative cell in the past, contained mucin granules with an electron-dense core, strong PAS reactivity, a special lectin-binding pattern, and localization of integumentary mucins FIM-B.1 and FIM-C.1. These results indicate that cone cells are a distinct cell type, elaborating and releasing particular mucins, and that functional heterogeneity of mucus-producing cells exists in the mucous skin glands of X. laevis.

Animals↗
PubMed1993

hP1.B, a human P-domain peptide homologous with rat intestinal trefoil factor, is expressed also in the ulcer-associated cell lineage and the uterus.

The six-cysteine P-domain motif forms the basic repeat unit of a growing family of mucin-associated peptides. A precursor for a human secretory polypeptide has been discovered by molecular cloning and deduced to have a single P-domain, termed hP1.B. The pre-pro-peptide has 67% amino acid identity with rat intestinal trefoil factor. We find, using the techniques of RNA analysis and in situ hybridization, that this P-domain peptide is expressed in the human gastrointestinal tract, where a number of pathological conditions affect its expression, and surprisingly find it is expressed in the uterus also. In the intestine, hP1.B is expressed by goblet cells, but in Crohn disease this peptide is synthesized and secreted additionally by the ulcer-associated cell lineage that is known to secrete two other trefoil peptides, pS2 and spasmolytic polypeptide (hSP). In the stomach, hP1.B mRNA is relatively scarce but is more abundant in foci of intestinal metaplasia and near to ulceration. Mucin-rich epithelial cells in hyperplastic polyps of the colon also express this peptide. The discovery of this P-domain peptide and its expression in association with mucins support the hypothesis that P-domains with mucins may subserve related functions in the maintenance and repair of mucosal function.

Amino Acid Sequence↗
PubMed1993

The P-domain or trefoil motif: a role in renewal and pathology of mucous epithelia?

By analogy with epidermal growth factor and EGF-like repeats, the P-domain, or trefoil motif, is a characteristic shuffled module containing six invariant cysteine residues that forms the basic unit for a family of mucin-associated peptides. These P-domain peptides are potential modulators of cell growth and they are also expressed under certain pathological conditions. Furthermore, P-domains have been found as components of extracellular mosaic proteins including certain mucins, where they are thought to play a role either in protein-protein or in lectin-like interactions.

Amino Acid Sequence↗