Molecular characterization of four intra-t mouse recombinants.
Molecular characterization of four intra-t mouse recombinants.
复制标题
四种小鼠体内重组体的分子特征。
DOI：
10.1007/bf02421539
复制
发表时间：
1989
期刊：
影响因子：
3.2
通讯作者：
Klein,J
中科院分区：
文献类型：
--
作者：
Mizuno,K;Vincek,V;Figueroa,F;Klein,J
在携带野生型和复合型染色体的杂合子中，小鼠 17 号染色体近端区域的重组大大减少。其原因是复合体中存在两个不重叠的反转。然而，罕见的交换确实发生在t/+杂合子的t复合体中。在这里，我们描述了四种特殊的内部重组子，tTu1 至 tTu4。为了绘制这四种重组体中基因交换的位置图，我们用特异于分布在复合体上的 16 个基因座的 DNA 探针对它们进行了分析。分析显示，在四个重组体中的三个中，两个倒位之间的短区域发生了相等的交换，产生仅携带近端倒位（tTu1和tTu4）或仅携带远端倒位（tTu2）的染色体。在第四个重组体（tTu3）中，在基因座D17Leh119和D17Leh66之间的近端倒位内发生不等交换，产生包含基因座Tcp-1、T和D17Tu5的区域被复制的染色体。 Brachyurylocus的重复导致抑制通常由该基因座上的显性(T)和隐性(tct)等位基因相互作用产生的尾巴缩短效应，使得T/tTu3小鼠具有正常的尾巴。
Recombination in the proximal region of mouse chromosome 17 is greatly reduced in heterozygotes carrying the wild-type and thetcomplex-type chromosomes. The reason for this is the presence of two non-overlapping inversions in thetcomplex. Rare crossing-over does, however, occur within thetcomplex of thet/+ heterozygotes. Here we characterize four such exceptional intra-trecombinants,tTu1throughtTu4. To map the positions of the genetic exchange in these four recombinants, we analyzed them with DNA probes specific for 16 loci distributed over thetcomplex. The analysis revealed that in three of the four recombinants, an equal crossing-over occurred in the short region between the two inversions, producing chromosomes carrying either the proximal inversion only (tTu1andtTu4) or the distal inversion only (tTu2). In the fourth recombinant (tTu3), unequal crossing-over occurred within the proximal inversion between lociD17Leh119andD17Leh66, producing a chromosome in which the region containing lociTcp-1, T, andD17Tu5has been duplicated. The duplication of theBrachyurylocus leads to the suppression of the tail-shortening effect normally produced by the interaction of the dominant (T) and recessive (tct) alleles at this locus so that theT/tTu3mice have normal tails.