2 ALPHA-TUBULIN GENES OF ASPERGILLUS-NIDULANS ENCODE DIVERGENT PROTEINS
2 ALPHA-TUBULIN GENES OF ASPERGILLUS-NIDULANS ENCODE DIVERGENT PROTEINS
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DOI：
10.1007/bf00282651
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发表时间：
1991-01-01
期刊：
影响因子：
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通讯作者：
MORRIS, NR
中科院分区：
文献类型：
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作者：
DOSHI, P;BOSSIE, CA;MORRIS, NR
我们分离并分析了构巢曲霉的tubA和tubB α-微管蛋白基因。 这些基因的核苷酸序列预测tubA的多肽为447个氨基酸，tubB为450个氨基酸。 预测的氨基酸序列在两种多肽之间表现出28%的差异。 这是第二个已知的情况下，这种高度分歧之间的α-微管蛋白在同一物种。 tubB基因的独特之处在于，它在通常的第二和第三个氨基酸之间编码一个额外的甘氨酸残基。 RNA印迹分析表明，tubA和tubB转录本各为1.8 kb长。 tubA转录水平在整个细胞周期中保持相同。tubB转录物的水平在细胞周期的任何特定阶段都不改变，但在孢子萌发期间持续增加。 tubA基因以前被定位到连锁群8，我们现在已经将tubB基因定位到连锁群4。 异核体中的基因破坏表明，tubA和tubB基因的破坏的表型后果是不同的。 tubA的分子破坏导致细胞核分裂受阻，而tubB则导致细胞和细胞核形态异常。
We have isolated and analyzed the tubA and tubB alpha-tubulin genes of Aspergillus nidulans. The nucleotide sequences of these genes predict polypeptides of 447 amino acids for tubA and 450 for tubB. The predicted amino acid sequences exhibit 28% divergence between the two polypeptides. This is the second known case of such high divergence between alpha-tubulins within the same species. The tubB gene is unique in that it codes for an extra glycine residue between what are usually the second and third amino acids. RNA blot analysis demonstrates that the tubA and tubB transcripts are each 1.8 kb long. The level of tubA transcript remains the same throughout the cell cycle. The level of tubB transcript does not change at any particular stage in the cell cycle but increases continuously during spore germination. The tubA gene was previously mapped to linkage group eight, and we have now mapped the tubB gene to linkage group four. Gene disruption in heterokaryons suggests that the phenotypic consequences of disruption are different for the tubA and tubB genes. Molecular disruption of tubA results in a block in nuclear division whereas in tubB it gives rise to abnormal cell and nuclear morphology.