Turnover of chloroplast and cytoplasmic ribosomes during gametogenesis in Chlamydomonas reinhardi

摘要: Abstract A number of novel observations on ribosomal metabolism were made during gametic differentiation Chlamydomonas reinhardi . Throughout the gametogenic process amount chloroplast and cytoplasmic ribosomes decreased steadily. The kinetics extent such decreases different for each two species. Comparable rRNA degradation accompanied this ribosome degradation. Concurrent with substantial was synthesis rRNA, proteins assembly new throughout gametogenesis. newly synthesized exhibited distinctively faster turnover than their counterpart. Cytoplasmic ribosomes, pulse-labeled in early stages, retained label until nearly complete even though a net decrease level continued, indicating that preferentially differentiation. Hence regulation gametogenesis contrasts conservation obtained vegetative growth C. other organisms. This unique pattern suggests is necessary some specific structural or functional difference relating to development stage life cycle might exist between degraded ribosomes.