Changing protein profiles in developing and germinating barley seeds

Though useful information on barley proteins exists from earlier studies, present attempt represents a concerted study with added information on changing protein levels during seed development and seed germination. Albumins represen ted the major proteins at 4 daf and were overtaken by glutelins on further development. Glob ulins increased gradually to decline after 30 daf while prolamins which were low initially became second highest from 25 daf onward. New polypeptides were observed in globulin fraction eve n at 40 daf, no changes occurred in prolamin and glutelin fractions after 20 daf. The intensity of globulin polypeptides decreased after 30 daf and that of glutelin and prolamin polypeptides incr eased even till 45 daf. During germination, globulins degraded by 5 th day but their degradation products stayed even on 10 th day. Polypeptides in glutelin and prolamin fractions and their degradation products were not seen after 5 th day thus suggesting a relatively more fulfilling s torage role for these fractions. Degradation of Mr 62 kDa albumin polypeptide by 4 th day pointed towards its storage function. Similar trends followed by prolamins and glutelins during accumulation and degradation vis-avis by globulins warrant further work on their mole cular mechanisms and on relevance of such varying trends in barley seed biology.