Persistence of chromosomal proteins HMG-14/-17 in myotubes following differentiation-dependent reduction of HMG mRNA

J M Pash, J S Bhorjee, B M Patterson, M Bustin
1990 Journal of Biological Chemistry  
The expression of chromosomal proteins HMG-14 and HMG-17 during cellular differentiation was studied in cultured mouse myoblasts. During myogenesis the level of both HMG-14 and HMG-17 mRNA decreased to less than 20% of that found in myoblasts. The down-regulation of HMG-14/-17 mRNA occurred simultaneously with activation of muscle-specific actin mRNA and was not linked to DNA synthesis, indicating that it is a differentiation-, rather than a cell cycle-related event. Incorporation of
more » ... d lysine into HMG proteins was similar to that into the major histone fractions in that it was significant in myoblasts and undetectable in myotubes. The decrease in mRNA and protein synthesis did not affect the cellular levels of HMG protein. These results indicate that the regulation of HMG-14/-17 mRNA levels is different from that of the histones and is linked to differentiation rather than to DNA synthesis.
pmid:1689723 fatcat:gkputidqajb47hs6u7eap2uxru