Mansour S J, Hoffman D C, Prescott D M
Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309-0347.
Gene. 1994 Jul 8;144(2):155-61. doi: 10.1016/0378-1119(94)90373-5.
We have isolated a gene-sized molecule encoding the catalytic subunit of DNA polymerase alpha from a macronuclear genomic library of Oxytricha nova, by using a 0.7-kb fragment of the corresponding human gene as a hybridization probe. Two different versions of the gene are present in the macronucleus, one with an EcoRI site (RI+) and one without an EcoRI site (RI-). The cloned RI- version has been characterized. It is 4938 bp in length, excluding telomeres. It consists of a 329-bp 5' leader, a 4479-bp coding region and a 130-bp 3' trailer. The deduced amino-acid sequence shares conserved regions with the yeast and human polypeptides. We also demonstrate by Southern analysis that gene-sized molecules of similar size, homologous to the isolated O. nova gene are present in the mac genome of closely and distantly related hypotrichs.
我们利用相应人类基因的一个0.7kb片段作为杂交探针，从新大核草履虫的大核基因组文库中分离出了一个编码DNA聚合酶α催化亚基的基因大小的分子。大核中存在该基因的两种不同版本，一种带有EcoRI位点（RI+），另一种没有EcoRI位点（RI-）。已对克隆的RI-版本进行了表征。它长度为4938bp，不包括端粒。它由一个329bp的5'前导序列、一个4479bp的编码区和一个130bp的3'尾序列组成。推导的氨基酸序列与酵母和人类多肽有保守区域。我们还通过Southern分析证明，在亲缘关系远近不同的下毛目动物的大核基因组中存在与分离出的新大核草履虫基因大小相似、同源的基因大小的分子。
