A Drosophila ribosomal protein functions in mammalian cells.
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ABSTRACT:
SUBMITTER: Maki CG
PROVIDER: S-EPMC361039 | biostudies-other | 1990 Sep
REPOSITORIES: biostudies-other
Publications
A Drosophila ribosomal protein functions in mammalian cells.
Maki C G CG Rhoads D D DD Diaz J J JJ Roufa D J DJ
Molecular and cellular biology 19900901 9
A cDNA expression vector encoding Drosophila ribosomal protein S14 was transfected into cultured Chinese hamster ovary (CHO) cells that harbor a recessive RPS14 emetine resistance mutation. Transformants synthesized the insect mRNA and polypeptide and consequently displayed an emetine-sensitive phenotype. These observations indicate that the insect protein was accurately expressed and correctly assembled into functional mammalian 40S ribosomal subunits. ...[more]
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Project description:The human WBSCR22 protein was previously shown to be up-regulated in invasive breast cancer and its ectopic expression enhances tumor cell survival in the vasculature. In the current study, we show that the WBSCR22 protein is important for cell growth. Knock-down of WBSCR22 with siRNA results in slower growth of WBSCR22-depleted cells. Treatment with siWBSCR22 causes defects in the processing of pre-rRNAs and reduces the level of free 40S ribosomal subunit, suggesting that WBSCR22 is involved in ribosome small subunit biosynthesis. The human WBSCR22 partially complements the growth of WBSCR22 yeast homologue, bud23 deletion mutant suggesting that the human WBSCR22 is a functional homologue of yeast Bud23. WBSCR22 is localized throughout the cell nucleus and is not stably associated with ribosomal subunits within the cell nucleus. We also show that the WBSCR22 protein level is decreased in lymphoblastoid cell lines derived from William-Beuren Syndrome (WBS) patients compared to healthy controls. Our data suggest that the WBSCR22 protein is a ribosome biogenesis factor involved in the biosynthesis of 40S ribosomal particles in mammalian cells.
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