CHARACTERIZATION OF A C-ALPHA GENE OF SWINE
CHARACTERIZATION OF A C-ALPHA GENE OF SWINE
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DOI：
10.1016/0161-5890(94)90171-6
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发表时间：
1994-06-01
影响因子：
3.6
通讯作者：
BUTLER, JE
中科院分区：
文献类型：
--
作者：
BROWN, WR;BUTLER, JE
测定了猪IgA重链恒定区的编码序列和生殖系基因的外显子-内含子结构。从猪肠系膜淋巴结cDNA文库中分离到一个跨越CH3结构域和部分CH2结构域的cDNA克隆(1A1)。将克隆1A1与聚合酶链式反应产生的DNA片段进行比对，该DNA片段包含CH1结构域至CH3结构域的5‘端，以获得完整的cDNA序列。与其他哺乳动物Cα重链(不包括铰链区)的比较表明，猪Cα推导的氨基酸序列与人Cα亚类的同源性最高(70%)，其次是小鼠Cα(61%)和13个兔Cα重链的共同序列(59%)。在所有物种中，CH3结构域之间的序列同源性最高。猪Cα的一个显著特征是其短小的6个氨基酸的铰链，与其他哺乳动物的免疫球蛋白一样，编码CH2结构域。对来自肝脏或精子DNA的生殖系Cα进行了序列分析，发现其外显子-内含子组织类似于其他哺乳动物的Cα基因。基因组Southern杂交数据与猪基因组中存在单一的Cα基因是一致的。这些研究中获得的数据将对在免疫学研究中使用猪作为模型有价值。
The cDNA sequence encoding the constant region of the porcine IgA heavy chain as well as the exon-intron structure of the germline gene, have been determined. A cDNA clone (1A1) spanning the CH3 domain and part of the CH2 domain was isolated from a porcine mesenteric lymph node cDNA library. Clone 1A1 was aligned with a PCR-generated DNA fragment encompassing the CH1 domain through the 5' end of the CH3 domain to derive the complete cDNA sequence. Comparison with other mammalian C alpha heavy chains (hinge regions excluded) indicated that the deduced amino acid sequence of porcine C alpha is most homologous with the human C alpha subclasses (> 70%), followed by mouse C alpha (61%) and a consensus sequence of the 13 rabbit C alpha heavy chains (59%). The greatest sequence homology was found among the CH3 domains in all species. A striking feature of porcine C alpha is its short six amino acid hinge which like other mammalian IgAs, is encoded with the CH2 domain. Sequence analysis of germline C alpha, generated by PCR from liver or sperm DNA, revealed an exon-intron organization similar to other mammalian C alpha genes. Genomic Southern blot data are consistent with the presence of a single C alpha gene within the porcine genome. Data obtained in these studies will be valuable in pursuing the use of swine as a model in immunological research.