Maguire M P, Paredes A M, Riess R W
Department of Zoology, University of Texas, Austin 78712.
Genome. 1991 Dec;34(6):879-87. doi: 10.1139/g91-135.
The phenotype of the desynaptic (dy) mutant of maize in microsporocytes at meiotic prophase was compared with normal microsporocytes of a closely related strain and with microsporocytes of a maize inbred line (KYS) assumed to be normal. Strikingly more univalents and open arms of bivalents were found in the mutant cells than in normal cells at diakinesis, and where there was heterozygosity for a distal knob (heterochromatic region), separation was usually equational, indicating the occurrence of normal crossing-over followed by failure of chiasma maintenance in the mutant. Differences found in the mutant by electron microscopy were a statistically significant wider dimension of the synaptonemal complex central region and also less twisting of synapsed configurations at pachytene. It is suggested that these are side-effect symptoms of a defect in the synaptonemal complex (or associated substance), which is expressed later as sporadic loss of chiasma maintenance.
将玉米去突触（dy）突变体在减数分裂前期的小孢子母细胞的表型，与一个近缘品系的正常小孢子母细胞以及假定为正常的玉米自交系（KYS）的小孢子母细胞进行了比较。在终变期，突变体细胞中发现的单价体和二价体的开放臂显著多于正常细胞，并且在存在远端纽结（异染色质区域）杂合性的情况下，分离通常是均等的，这表明在突变体中发生了正常的交叉互换，随后出现交叉维持失败。通过电子显微镜在突变体中发现的差异包括，联会复合体中央区域在统计学上具有显著更宽的尺寸，并且在粗线期联会构型的扭曲也更少。有人认为，这些是联会复合体（或相关物质）缺陷的副作用症状，该缺陷随后表现为交叉维持的偶发性丧失。
