Background Mucins are large glycoproteins that cover epithelial surfaces of the body. a protein similar to Muc2, but it is lacking a PTS domain. We also show that the -subunit of ovomucin is the orthologue of human MUC6. The transmembrane em Muc13 /em gene is in chicken as well as in mammals adjacent to the em HEG /em (heart of glass) gene. HEG has PTS, EGF and transmembrane domains like Muc13, suggesting that these two proteins are evolutionary related. Unlike previously known mucins, the PTS domain of Muc13 is encoded by multiple exons, where each exon encodes a repeat unit of the PTS domain. Conclusion We report new mucin homologues in chicken and this information will aid in understanding the evolution of mucins in vertebrates. The fact that ovomucin, a protein not found in mammals, was located in the same locus as other gel-forming mucins provides strong support that these proteins are evolutionary related. Furthermore, a relationship of HEG and the transmembrane Muc13 is suggested on the basis of their biochemical properties and their existence in the same locus. Finally, our discovering that the poultry Muc13 can be distributed between multiple exons raises the interesting probability that along the PTS domain could Rabbit polyclonal to INPP4A possibly be managed by substitute splicing. History The mucosal areas are all included in mucus largely comprised of the huge glycoproteins known as mucins. Mucins play a significant role in safety, however, many mucins also be a part of cell surface area signaling and so are very important to cancer advancement and progression. Normal for 2-Methoxyestradiol pontent inhibitor the mucins will be the huge mucin (PTS) domains abundant with the proteins Ser, Thr and Pro, often seen as a ideal or imperfect tandem repeats [1]. Many mucins likewise have additional characteristic domains such as for example von Willebrand D (VWD) or Ocean (ocean urchin sperm protein-enterokinase-agrin) domains. We’ve developed bioinformatics solutions to determine and characterize mucin genes predicated on these specific properties of mucins [2]. Using such methods, we lately completed an evaluation of the puffer seafood em Fugu rubripes /em [2]. You can find two main types of mucins, membrane-bound and secreted. In human being, nine membrane-bound (MUC1, MUC3A, MUC3B, MUC4, MUC12, MUC13, MUC16 and MUC17) [3-9] and seven secreted mucins (MUC2, MUC5B, MUC5AC, MUC6, MUC7, MUC19 and MUC20) [10-16] have already been recognized. The secreted mucins could be additional sub-divided to be either gel-forming (MUC2, MUC5B, MUC5AC, MUC6 and MUC19) or not 2-Methoxyestradiol pontent inhibitor really (MUC7 and MUC20). The opportunity to type gels would depend on the capability of monomers to create polymeric structures. Gel-forming mucins possess three VWD domains within their N-terminal ends which are involved with polymerization through intermolecular 2-Methoxyestradiol pontent inhibitor disulfide-bonds. There is also a cysteine-knot (CK) domain at their C-terminal ends (examined in [17]). The VWD domain was initially recognized in the prepro-von Willebrand element [18], therefore its name. The gel forming mucins and the von Willebrand element dimerize by using their C-terminal VWD domains in the endoplasmic reticulum (ER) [17-19] and oligomerize through their N-terminal VWD domains in the acidic compartments of the Golgi complicated [17,20]. The human being transmembrane mucins are characterized by the Ocean domain or a particular variant of the VWD domain that’s lacking cysteines. Many of the human being transmembrane mucins are recognized to or predicted to be cleaved in their SEA or VWD domains [21]. To understand the evolution of mucins, we are systematically examining the distribution and structure of mucins in different organisms. The results of such analysis will ultimately provide a better understanding of the function of the human mucins. It is also important to study 2-Methoxyestradiol pontent inhibitor mucins from organisms such as em C. elegans /em , 2-Methoxyestradiol pontent inhibitor em Drosophila /em , zebrafish and mouse as these are important experimental model systems. The previously analyzed puffer fish em Fugu rubripes /em [2] has a gene repertoire similar in size to that of man, but according to our analysis it seems to lack several of the mucins found in the human genome. In particular, this is the case for the transmembrane mucins as only one such gene was identified in the fish whereas the human genome encodes at least nine different. Sequencing and annotating mucin genes is notoriously difficult due to their large size and repetitive nature. Therefore, the identification and classification of putative novel mucins requires a variety of bioinformatics tools as well as expert biological knowledge. Continuing our analysis of animal mucin genes, we now report.