title: IHH and FGF8 coregulate elongation of digit primordia.
abstract: In the developing limb bud, digit pattern arises from anterior-posterior (A-P) positional information which is provided by the concentration gradient of SHH. However, the mechanisms of translating early asymmetry into morphological form are still unclear. Here, we examined the ability of IHH and FGF8 signaling to regulate digital chondrogenesis, by implanting protein-loaded beads in the interdigital space singly and in combination. We found that IHH protein induced an elongated digit and that FGF8 protein blocked the terminal phalange formation. Molecular marker analysis showed that IHH expanded Sox9 expression in mesenchymal cells possibly through up-regulated FGF8 expression. Application of both IHH and FGF8 protein induced a large terminal phalange. These results suggest that both enhanced IHH and FGF8 signaling are required for the development of additional cartilage element in limbs. IHH and FGF8 maybe play different roles and act synergistically to promote chondrogenesis during digit primordia elongation.
authors: Bio-X Center, Shanghai Jiao Tong University, Shanghai, China.
authors: Jian
authors: J
authors: Zhou
authors: Junwei
authors: J
authors: Meng
authors: Shengzhen
authors: S
authors: Guo
authors: Bo
authors: B
authors: Gao
authors: Gang
authors: G
authors: Ma
authors: Xuming
authors: X
authors: Zhu
authors: Jianxin
authors: J
authors: Hu
authors: Yue
authors: Y
authors: Xiao
authors: Chuwen
authors: C
authors: Lin
authors: Hongsheng
authors: H
authors: Wang
authors: Lusheng
authors: L
authors: Ding
authors: Guoyin
authors: G
authors: Feng
authors: Xizhi
authors: X
authors: Guo
authors: Lin
authors: L
authors: He
mesh_terms: D000818:Animals; D002356:Cartilage / Q000196:embryology / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D002642:Chick Embryo; D002645:Chickens; D020219:Chondrogenesis / Q000235:genetics / Q000502:physiology; D051524:Fibroblast Growth Factor 8 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D053823:Hedgehog Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D017403:In Situ Hybridization; D018878:Limb Buds / Q000166:cytology / Q000196:embryology* / Q000378:metabolism
chemical_list: D053823:Hedgehog Proteins; D051524:Fibroblast Growth Factor 8