Here, we use GHR ubiquitination to measure progression of the GHR in the endocytosis process.
The increase was solely due to decreased endocytosis of the mature (130kD) GHR, because the steady state levels of GHR in the endoplasmic reticulum (110kD) were unchanged.
The differences between species indicate possible effects of selective sweeps before domestication (GHR in pigs) or before species divergence (GHR in Bison), directional (artificial) selection (PRLR in pigs) or functional switching (GHR in cattle, PRLR).
Several authors have postulated a divergent evolution of salmonid GHRs (GHR type II); however, it has recently been cloned a GHR in rainbow trout (Oncorhynchus mykiss), which is analogous to GHRs of non-salmonid fish (GHR type I) and a GHR type II in non-salmonid fish [ 11].
Thus, GPI anchoring of GH or ecGHR increases the probability that the GPI-anchored proteins will co-segregate with the native GHR on the cell membrane and constrain the GHR in a conformation that cannot be readily internalized.
The challenge of implementing research was not unique to these teams or to GHR in general, however, the problem seemed especially acute in GHR given the paradoxical widening gap in health status between populations at the same time as increasing investment in international health and GHR.
