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L Goldstein

Publications and source records attributed to L Goldstein.

At least 271 records · Page 15Linked to original sources
PubMed1970

Characterization of RNAs that do and do not migrate between cytoplasm and nucleus.

We have investigated the nature of the RNA that moves from cytoplasm to nucleus against a concentration gradient in Amoeba proteus. We find that: In the presence of actinomycin D an unlabeled nucleus grafted into a [(3)H]RNA cytoplasm acquires RNAs with sedimentation constants 30 S, 19 S, and 4-6S that are not related to the general population of cytoplasmic ribosomal and transfer RNAs. RNAs of sedimentation constants 39 S and 16 S may also enter the nucleus from the cytoplasm, but not in the presence of actinomycin D. Nuclei were transplanted from [(3)H]RNA cells through several unlabeled cytoplasms to dilute out migrating [(3)H]RNA. This resulted in the 4-6 S [(3)H]RNA being retained as the predominant labeled material of the nucleus and establishes that a substantial portion of 4-6S nuclear RNA does not leave the interphase nucleus. We conclude that nuclear RNAs may be classified in a new way: (1) RNA that is to become cytoplasmic RNA and presumably moves only from nucleus to cytoplasm; (2) RNA that migrates back and forth between nucleus and cytoplasm; and (3) RNA that does not leave the nucleus during interphase.

Amoeba↗