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541.
Hybrid polar compounds (HPCs), such as suberoylanilide hydroxamic acid (SAHA), induce differentiation of transformed cells. Differential display of RNA was used to identify genes whose expression is changed during SAHA-induced differentiation of murine erythroleukemia (MEL) cells. One such cDNA was identified whose mRNA level decreased by 50% after 8h of SAHA treatment as determined by Northern blot analysis. The full-length cDNA (1944bp in length) was cloned by sequencing of an EST clone and rapid amplification of 5' cDNA ends (5'-RACE). The predicted amino acid sequence is 589 amino acids and shares 45% identity with the yeast cytoplasmic phenylalanyl tRNA synthetase (PheRS) regulatory alpha-subunit. Human EST clones which share over 90% identity of predicted amino acid sequence with this cDNA map to chromosome 2 near the paired box homeotic gene 3 (PAX3) locus, a region syngenic to mouse chromosome 1. This is the first report of the cloning of the full-length cDNA for the murine PheRS regulatory alpha-subunit-like protein. The level of PheRS alpha-subunit-like mRNA is regulated during differentiation but not during cell cycle progression. 相似文献
542.
Dong Tu Nguyen Tuan Cuong Ngo Huy Hoang Tran Thi Phuong Lan Nguyen Binh Minh Nguyen Kouichi Morita & Masahiko Ehara 《FEMS microbiology letters》2009,298(1):37-43
Autoagglutinable strains of Vibrio cholerae O1 (seven nonfimbriate strains and one fimbriate strain) were transformed to obtain resistance to ampicillin. Two distinct mechanisms were found in these strains. One was operating in nonfimbriate strains by reducing OmpU protein production and the other was operating in a fimbriate strain (Bgd17) by newly overproducing cpxP protein. The twitching motility in the fimbriate Bgd17 strain disappeared depending on the production of cpxP protein, suggesting that fimbriation of V. cholerae O1 is controlled by a two-component signal transduction system. 相似文献
543.
Serum samples were analyzed for their urea content using fluorescence flow injection analysis incorporating an immobilized urease bioreactor and a gas permeable separator. The urease was immobilized under mild and facile conditions to a hydrophilic 2-fluoro-1-methylpyridinium-activated support. The ammonia released as a result of urease-catalyzed urea hydrolysis diffused through a gas permeable membrane into a constant stream of o-phthaldehyde solution to form a highly fluorescent product with lambda ex at 340 nm and lambda em at 455 nm. Up to 25 serum samples can be analyzed per hour. The within-day coefficient of variation (CV) was 1.12% and the day-to-day CV was 1.25% for serum containing 10.50 mg urea nitrogen dl-1. The bioreactor shows excellent storage (at 4 degrees C) and operational stabilities (at 37 degrees C). 相似文献