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981.
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Sugita Mamoru; Luo Lijun; Ohta Masaru; Itadani Hiraku; Matsubayashi Tohru; Sugiura Masahiro 《DNA research》1995,2(2):71-76
A part of the tRNALeu (UAA) gene containing a 240-nucleotidegroup I intron was amplified by PCR from cyanobacterium SynechococcusPCC 6301 genomic DNA. The pre-tRNA synthesized from the clonedPCR product was efficiently self-spliced in vitro under physiologicalconditions. The gene encoding the tRNALeu (UAA), trnL-UAA, wasisolated from a Synechococcus PCC 6301 genomic library and thenucleotide sequence of a 2,167-bp portion was determined. ThetrnL-UAA consists of a 34-bp 5' exon, a 240-bp group I intronand a 50-bp 3' exon. In addition, three open reading frames(ORF1, ORF2 and ORF3) were found in the 5' and 3' flanking regionsof trnL-UAA. The predicted protein sequence of ORF3, which islocated 74-bp upstream from trnL-UAA on the opposite strand,shows 66.2% amino acid identity to that of the SynechocystisPCC 6803 gene encoding subunit L of NADH dehydrogenase (ndhL). 相似文献
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Reproductive behavior and mating systems of the triggerfish,Sufflamen chrysopterus (Balistidae), were studied on the fringing reef of Sesoko Island, Okinawa. Both males and females maintained territories
against consexual adults, feeding on benthic animals within their own territories. Each male territory overlapped one or two
female territories, with mating occurring between the cohabitants. The monogamous males were smaller and foraged more frequently
than the bigamous ones, suggesting that the former allocated more energy to growth rather than to improving reproductive success.
Pair spawning occurred around sunrise, females only taking care of the demersal eggs until hatching, which occurred around
sunset of the same day. On spawning days females foraged less frequently than usual, but as frequently as males. Females spawned
at intervals of 5–7 days, usually shifting sites within their territories. Thus both feeding and spawning sites were available
for females within their territories, providing males with the opportunity to monopolize females by defending their territories. 相似文献
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988.
Koichi Kuwano Saori Ono Akira Akashi Masahiro Ohishi Hideki Shigematsu Sumio Arai 《Microbiology and immunology》1997,41(3):261-264
The role of cellular immunity in mycoplasma infection is not completely understood. In this study, we established mycoplasma-specific T-cell clones to evaluate cellular immunity in mycoplasma infection. We developed a T-cell clone (G-10) which was stimulated with Acholeplasma laidlawii. The T-cell clone G-10, CD4+ and T-cell receptor (TCR) αβ+ recognized the 42- and 65-kilodalton (kDa) membrane proteins of A. laidlawii and responded to A. hippikon. Hence, the application of mycoplasma-specific T cells such as G-10 in animal models may allow the assessment of cellular immune response to mycoplasma infection. 相似文献
989.
990.