IDA4-1, IDA4-2, AND IDA4-3 ARE INTRON SPLICING MUTATIONS AFFECTING THE LOCUS ENCODING P-28, A LIGHT-CHAIN OF CHLAMYDOMONAS AXONEMAL INNER DYNEIN ARMS
IDA4-1, IDA4-2, AND IDA4-3 ARE INTRON SPLICING MUTATIONS AFFECTING THE LOCUS ENCODING P-28, A LIGHT-CHAIN OF CHLAMYDOMONAS AXONEMAL INNER DYNEIN ARMS
复制标题
DOI：
10.1091/mbc.6.6.713
复制
发表时间：
1995-06-01
影响因子：
3.3
通讯作者：
PIPERNO, G
中科院分区：
文献类型：
--
作者：
LEDIZET, M;PIPERNO, G
我们最近确定了编码p28基因的核苷酸序列，p28是衣藻轴突内动力蛋白臂的轻链。在这里，我们发现p28是由IDA4位点编码的蛋白质。在ida4的3个等位菌株（ida4-1、ida4-2和ida4-3）的鞭毛和细胞体中完全不存在P28及其相关的动力蛋白重链。我们确定了p28基因的三个等位基因的核苷酸序列，发现在每种情况下都有一个核苷酸变化，分别影响第一，第二和第四个内含子的剪接位点。逆转录-聚合酶链反应扩增从ida4细胞制备的rna证实，这些突变阻止了受影响的内含子的正确剪接，从而阻断了全长p28的合成。这是第一个在衣藻中描述的内含子剪接突变，也是第一个在分子水平上表征的内动力蛋白臂突变。通常与p28相关的动力蛋白重链在ida4轴突体中缺失，这表明p28对于动力蛋白内臂子集的稳定组装或这些臂与微管双联体的结合是必要的。
We recently determined the nucleotide sequence of the gene encoding p28, a light chain of inner dynein arms of Chlamydomonas axonemes. Here, we show that p28 is the protein encoded by the IDA4 locus. p28, and the dynein heavy chains normally associated with it, are completely absent from the flagella and cell bodies of three allelic strains of ida4, named ida4-1, ida4-2, and ida4-3. We determined the nucleotide sequence of the three alleles of the p28 gene and found in each case a single nucleotide change, affecting the splice sites of the first, second, and fourth introns, respectively. Reverse transcriptase-polymerase chain reaction amplification of RNAs prepared from ida4 cells confirmed that these mutations prevent the correct splicing of the affected introns, thereby blocking the synthesis of full-length p28. These are the first intron splicing mutations described in Chlamydomonas and the first inner dynein arm mutations characterized at the molecular level. The absence in ida4 axonemes of the dynein heavy chains normally found in association with p28 suggests that p28 is necessary for stable assembly of a subset of inner dynein arms or for the binding of these arms to the microtubule doublets.