Reference

Anti-mRNA: specific inhibition of translation of single mRNA molecules

Anti-mRNA: specific inhibition of translation of single mRNA molecules. Pestka, Sidney; Daugherty, Bruce L.; Jung, Vincent; Hotta, Kunimoto; Pestka, Robert K. (Roche Res. Cent., Roche Inst. Mol. Biol., Nutley, NJ 07110, USA). Proc. Natl. Acad. Sci. U. S. A., 81(23), 7525-8 (English) 1984. CODEN: PNASA6. ISSN: 0027-8424. DOCUMENT TYPE: Journal CA Section: 3 (Biochemical Genetics) Section cross-reference(s): 6 A plasmid was constructed to generate RNA, which is complementary to the b-galactosidase [9031-11-2] mRNA of Escherichia coli, under control of the phage l PL promoter. When this anti-mRNA was produced, synthesis of b-galactosidase was dramatically inhibited (98%). Syntheses of lactose permease [9068-45-5] and thiogalactoside transacetylase [9029-94-1], the coding sequences of which are downstream of the b-galactosidase coding region, are inhibited to a lesser degree, 80% and 55%, resp. The generation of anti-mRNA that can be targeted to inhibit a single species of mRNA mol. within cells provides a potent mechanism by which specific transcripts can be translationally inactivated. This can be used to det. the function of proteins as well as to select cloned genes in a single rapid and convenient step.

Identification of the secY (prlA) gene product involved in protein export in Escherichia coli

Identification of the secY (prlA) gene product involved in protein export in Escherichia coli. Ito, Koreaki (Inst. Virus Res., Kyoto Univ., Kyoto 606, Japan). MGG, Mol. Gen. Genet., 197(2), 204-8 (English) 1984. CODEN: MGGEAE. ISSN: 0026-8925. DOCUMENT TYPE: Journal CA Section: 3 (Biochemical Genetics) The gene secY (or prlA) is essential for protein export across the cytoplasmic membrane of E. coli. The protein product of secY was identified using the gene cloned under the control of the pL promoter of phage l in combination with the maxicell system. The protein had some unusual properties. First, it is important not to heat the protein at 100° in the SDS sample buffer for its subsequent detection by gel electrophoresis. Second, migration of the protein in SDS-polyacrylamide gel electrophoresis is variable depending on the gel compns. Gels with stronger sieving effect give higher apparent mol. wts. These properties are similar to those of hydrophobic proteins of the cytoplasmic membrane, such as the lactose permease [9068-45-5]. Finally, a major fraction of the protein synthesized from the overproducing plasmid is degraded rapidly in vivo. The altered protein from the secY24 mutant gene is even more unstable. These results provide information which is basic for the dissection of the protein export machinery of the bacterial cell.