Transfer RNA methylases during morphogenesis in the cellular slime mold.
نویسندگان
چکیده
The enzymes that methylate tRNA were studied during the life cycle of the colonizing slime mold, Dictyostelium discoideum. Total and base specific tRNA methylase activities were determined in extracts from cells in morphogenetic synchrony. Eight hours after enforced aggregation, the total methylase capacity is reduced by about 40 per cent. The diminution appears to be due to the presence of inhibitors that do not inhibit the base specific enzymes to the same extent. There is a still greater diminution in enzyme activity in extracts of the mature fruiting bodies.
منابع مشابه
Inhibitor of transfer ribonucleic acid methylase in the differentiating slime mold Dictyostelium discoideum.
Eight hours after the onset of morphogenesis, an inhibitor of transfer ribonucleic acid methylases appears in differentiating Dictyostelium discoideum. The inhibitor is also present in spores. Fifty per cent of the inhibiting activity is lost upon heating at 100 C for 5 min; it is nondialyzable and sensitive to trypsin.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 62 4 شماره
صفحات -
تاریخ انتشار 1969