Y Lawrence Livermore National Laboratory below Contract DE- AC52-07NA27344. The content material is solely the responsibility with the authors and does not necessarily represent the official views from the National Institutes of Well being. The funders had no function in study design and style, data collection and analysis, choice to publish, or preparation on the manuscript.Author Manuscript Author Manuscript Author Manuscript Author Manuscript
www.nature.com/scientificreportsOPENDisruption of c-Kit Signaling in KitW-sh/W-sh Expanding Mice Increases Bone TurnoverSutada Lotinun1,2 Nateetip Krishnamrac-Kit tyrosine kinase receptor has been identified as a regulator of bone homeostasis. The c-Kit loss-offunction mutations in WBB6F1/J-KitW/W-v mice lead to low bone mass. Having said that, these mice are sterile and it can be unclear whether or not the observed skeletal phenotype is secondary to a sex hormone deficiency. In contrast, C57BL/6J-KitW-sh/W-sh (Wsh/Wsh) mice, which carry an inversion Bcl-B Purity & Documentation mutation affecting the transcriptional regulatory elements from the c-Kit gene, are fertile. Here, we showed that Wsh/Wsh mice exhibited osteopenia with elevated bone resorption and bone formation at 6- and 9-week-old. The c-Kit Wsh mutation elevated osteoclast differentiation, the number of committed osteoprogenitors, alkaline phosphatase activity and mineralization. c-Kit was expressed in both osteoclasts and osteoblasts, and c-Kit expression was decreased in Wsh/Wsh osteoclasts, but not osteoblasts, suggesting an indirect effect of c-Kit on bone formation. In addition, the osteoclast-derived coupling factor Wnt10b mRNA was increased in Wsh/Wsh osteoclasts. Conditioned medium from Wsh/Wsh osteoclasts had elevated Wnt10b protein levels and induced elevated alkaline phosphatase activity and SHP2 Storage & Stability mineralization in osteoblast cultures. Antagonizing Wnt10b signaling with DKK1 or Wnt10b antibody inhibited these effects. Our data suggest that c-Kit negatively regulates bone turnover, and disrupted c-Kit signaling couples increased bone resorption with bone formation by means of osteoclast-derived Wnt 10 b. c-Kit, a receptor tyrosine kinase belonging for the platelet-derived development aspect (PDGF) and the colony-stimulating element 1 (CSF-1) receptor family members, is really a item on the gene at the Dominant White Spotting (W) locus1,2. The ligand for c-Kit is the gene product on the Steel (Sl) locus and is called mast cell development element, stem cell issue, steel element, and Kit ligand (KL)three,4. c-Kit and KL are vital for regular development and maintenance of three stem cell populations: germ cells, neural crest erived melanocytes, and hematopoietic stem cells. c-Kit is present in primordial germ cells, spermatogonia, primordial oocytes, expanding oocytes, melanocytes5, mast cells6, and osteoclasts7. Homozygotes carrying mutations in the W and Sl loci are erythrocyte- and mast cell-deficient, infertile, and lack pigmented coats8. Many naturally occurring loss-of-function mutations of c-Kit have already been identified in mice and humans. The W mutation is usually a null mutation causing deletion with the transmembrane domain of the c-Kit receptor, although Wv is actually a point mutation inside the kinase domain with the receptor resulting in impaired receptor activity9. Cells expressing the Wv mutation do not respond to KL in proliferation and apoptosis assays, presumably as a result of the inability of the receptor to initiate signal transduction102. W-sash (Wsh), an allele of W, is definitely an inversion mutation upstream of your c-Kit promoter area affecting a crucial reg.

By mPEGS 1