Neutral theory of molecular evolution

Developed by Motoo Kimura, who argued that most of the evolution of DNA sequences occurs by chance (genetic drift) rather than by natural selection. 

TLS Online TPP Program

#Id: 9346

#XL - T Zoology

The prodomains of TGF-β1 and TGF-β3 contain a RGD motif, that allows them to bind to integrins.

TLS Online TPP Program

#Id: 9347

#XL - T Zoology

During cell migration, a tensile force is generated which physically distorts the prodomain and frees the active TGF-β dimer, initiating TGF-β signaling.

TLS Online TPP Program

#Id: 9348

#XL - T Zoology

3 separate TGF-β receptor proteins participate in binding TGF-β and activating signaling:

RI, RII, and RIII

TLS Online TPP Program

#Id: 9350

#XL - T Zoology

RI and RII receptors are homodimeric proteins with serine/threonine kinases in their cytosolic domains. 

(RI and RII sufficient to serve as a functional hetero-tetrameric TGF-β receptor)

TLS Online TPP Program

#Id: 9351

#XL - T Zoology

RII exhibits constitutive kinase activity; means it is active even when not bound to TGF-β.

TLS Online TPP Program

#Id: 9352

#XL - T Zoology

RIII, also called β-glycan, is a cell-surface proteoglycan.