Abstract
BackgroundFibin was initially discovered as a secreted signal molecule essential for pectoral fin bud initiation in zebrafish. Currently, there is little information about the molecular architecture and biological relevance of fibin in humans and other mammals.ResultsFibin is expressed in cerebellum, skeletal muscle and many other embryonic and adult mouse tissues suggesting not only a role during embryonic development but also in adult functions. A 2.5-kbp genomic sequence fragment upstream of the coding sequence is sufficient to drive and regulate fibin expression through stimulation by glucocorticoids, activators of the protein kinase C signalling pathways and manganese ions. Fibin is an evolutionarily conserved protein, carries a cleavable signal peptide (amino acids 1-18) and is glycosylated at Asn30. The two conserved cysteines participate in intermolecular disulfide bond and multimer formation. Although fibin displays all features of a secretory protein, it is mostly retained in the endoplasmic reticulum when heterologously expressed.ConclusionFibin is functionally relevant during embryogenesis and adult life. Its expression is regulated by a number of cellular signalling pathways and the protein is routed via the secretory pathway. However, proper secretion presumably requires an unknown covalently-linked or associated co-factor.
Highlights
Fibin was initially discovered as a secreted signal molecule essential for pectoral fin bud initiation in zebrafish
The findings suggest that fibin is essential for the pectoral fin bud formation during embryogenesis
Fibin is routed through the endoplasmic reticulum (ER) we found no significant evidence of secretion
Summary
Fibin was initially discovered as a secreted signal molecule essential for pectoral fin bud initiation in zebrafish. There is little information about the molecular architecture and biological relevance of fibin in humans and other mammals. A secreted protein, was recently described as a novel growth factor found in various embryonic tissues of zebrafish and in the forelimb buds of mouse embryos [1]. The functional knockdown of fibin resulted in an absence of pectoral fins [1]. Fibin induces the expression of tbx via an unknown signalling cascade [1]. The findings suggest that fibin is essential for the pectoral fin bud formation during embryogenesis.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
