BIO380H5 Lecture Notes - Lecture 20: Lateral Plate Mesoderm, Limb Bud, Paraxial Mesoderm
Document Summary
Transplantation of different: the paraxial mesoderm is determining where the limb field will form, the purpose (cid:449)as to spe(cid:272)ifi(cid:272)all(cid:455) , the de(cid:272)isio(cid:374) as to (cid:449)hi(cid:272)h so(cid:373)ites is depe(cid:374)da(cid:374)t o(cid:374) the ho(cid:454) ge(cid:374)es. If (cid:455)ou re(cid:373)o(cid:448)e ra, it should(cid:374)"t (cid:271)e surprisi(cid:374)g that the fgf8 e(cid:454)pressio(cid:374) e(cid:454)pa(cid:374)ds (cid:373)ore to(cid:449)ards the middle of the ap axis. Looking at (c : for limb development, this is a marker for a limb transcription factor, tbx5, which marks the forelimb. Fgf10 is then expressed in the lateral plate mesoderm where the limbs will form forelimbs and the hindlimbs and very active in the brain limb. Fgf10 gets turned on in response to the expression of 2 tbx transcription factors: ra initiates the level specific expression of these 2 tbx tfs, this is happening in the lateral plate mesoderm which is just underneath ectoderm. Fgf(cid:1005)(cid:1004) (cid:272)a(cid:374) pro(cid:373)ote li(cid:373)(cid:271) (cid:271)ud gro(cid:449)th (cid:449)here(cid:448)er its pla(cid:272)ed, it"s a (cid:448)er(cid:455) pote(cid:374)t i(cid:374)du(cid:272)er of li(cid:373)(cid:271) (cid:271)ud formation.
