Molecular and functional analysis of the mariner mutator element Mos1 in Drosophila.
Molecular and functional analysis of the mariner mutator element Mos1 in Drosophila.
复制标题
DOI：
--
复制
发表时间：
1991-06
期刊：
影响因子：
3.3
通讯作者：
M. Medhora;K. Maruyama;D. Hartl
中科院分区：
文献类型：
--
作者：
M. Medhora;K. Maruyama;D. Hartl
果蝇的白桃等位基因源于转座因子mariner的插入。插入到white-peach中的特定副本是称为peach元素的非活动副本。在基因组其他位置存在mariner活性拷贝的情况下，桃元素的切除率很高，体细胞中桃元素的切除在表型上是通过白桃果蝇眼睛颜色镶嵌现象的发生来识别的。通过诱导白桃高水平嵌合而鉴定出的活性海洋元素被称为Mos （Mosaic）因子。我们对最初在毛里求斯果蝇中发现的因子Mos1进行了测序和功能分析。Mos1元件的长度为1286个碱基对，与peach元件的长度相同。它与peach元件在整个长度上分布的11个核苷酸位置不同，包括长开放阅读框中的4个氨基酸替换。Mos1与桃的嵌合结构分析表明，Mos1的5′和3′部分在功能上存在重要差异。与Mos1序列相同的较靠近的元件在转化子中产生较低水平的嵌合，这意味着相邻的侧翼序列对Mos1活性有重要影响。另一种被命名为Ma351的水手基因，从毛利亚菌的非镶嵌菌株中分离出来，与Mos1仅在三个核苷酸位置上不同。当引入种系时，Ma351根据插入位置产生不同水平的白桃镶嵌。这些结果表明，水手元件的活性是由它们自己的核苷酸序列、相邻的侧翼序列的影响以及更远距离的位置影响共同决定的。
The white-peach allele in Drosophila results from insertion of the transposable element mariner. The particular copy that is inserted in white-peach is an inactive copy referred to as the peach element. The peach element is excised at a high rate in the presence of active copies of mariner located elsewhere in the genome, and the excision of peach in somatic cells is recognized phenotypically by the occurrence of eye-color mosaicism in white-peach flies. Active mariner elements identified by their ability to induce high levels of white-peach mosaicism are denoted Mos (Mosaic) factors. We have sequenced and functionally analyzed the factor Mos1 originally identified in Drosophila mauritiana. The Mos1 element is 1286 base pairs in length, the same length as the peach element. It differs from the peach element in 11 nucleotide positions distributed throughout its length, including four amino acid replacements in the long open reading frame. Analysis of chimeric constructs between Mos1 and peach implies that functionally important differences occur in both the 5' and 3' halves of Mos1. A mariner element identical in sequence to Mos1 yields lower levels of mosaicism in transformants, implying that adjacent flanking sequences have important effects on Mos1 activity. Another mariner element, designated Ma351, isolated from a nonmosaic strain of D. mauritiana, differs from Mos1 in just three nucleotide positions. When introduced into the germline, Ma351 yields various levels of white-peach mosaicism depending on insertion site. These results imply that the activity of mariner elements is determined jointly by their own nucleotide sequences, by the effects of adjacent flanking sequences, and by longer-range position effects.