Molecular biology of the genes for immobilization antigens in Paramecium.
Molecular biology of the genes for immobilization antigens in Paramecium.
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草履虫固定抗原基因的分子生物学。
DOI：
10.1111/j.1550-7408.1987.tb03205.x
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Barnett,A
中科院分区：
文献类型：
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作者：
PreerJr,JR;Preer,LB;Rudman,B;Barnett,A
已分离出几种草履虫复合体表面抗原基因。除了已知的51A基因缺失外，我们还获得了涉及51B基因的缺失，并开发了获得其他基因缺失的方法。已发现A和B基因的孟德尔和非孟德尔缺失。在非孟德尔缺失中，基因存在于微核中，而不存在于大核中。在接合和自配时，微核DNA加工成新的大核DNA是在旧大核的控制下，新形成的大核变得与旧大核完全一样。因此，在非孟德尔突变体中，大核具有缺失的特异性抗原基因，并且在下一次接合或自配时指导正常DNA加工的能力也受损。这些例子，沿着其他例子，表明这种大核控制系统是纤毛虫遗传学的一个基本特征。对51A和51C基因的序列进行了描述，并与其他人获得的156G和51H基因进行了比较。51A和156G基因非常相似，而51C和51H则有很大差异。没有观察到内含子或假基因。一些，可能是所有的基因都在染色体的末端。给出了与基因编码部分相邻的特征性上游和下游序列。对于谷氨酰胺，序列UAA和UAG优于CAA和CAG，而UGA是真正的终止密码子。
Several genes for surface antigens of theParamecium aureliacomplex of species have been isolated. In addition lo known deletions of the 51A gene, we have obtained deletions involving the 51B gene and have developed a procedure for obtaining deletions of additional genes. Both Mendelian and non‐Mendelian deletions of both the A and B genes have been found. In the non‐Mendelian deletions the genes are present in the micronuclei and absent in the macronuclei. Processing of micronuclear DNA into new macronuclear DNA at conjugation and autogamy is under the control of the old macronucleus, and newly forming macronuclei become exactly like the old. Thus in the non‐Mendelian mutants, macronuclei have a specific antigen gene deleted and also are impaired in their ability to direct normal DNA processing at the next conjugation or autogamy. These cases, along with others, show that this system of macronuclear control is a fundamental feature of ciliate genetics. The sequence of the 51A and 51C genes is described and compared with the 156G and 51H genes obtained by others. The 51A and 156G genes are remarkably similar while 51Cand 51H are rather different. No introns or pseudogenes have been observed. Some, possibly all, of the genes are on the ends of chromosomes. Characteristic upstream and downstream sequences adjacent to the coding portions of the genes are given. The sequences UAA and UAG are preferred over CAA and CAG for glutamine while UGA is the true stop codon.