构巢曲霉有性杂交过程中核外基因的传递与重组

Transmission and recombination of extranuclear genes during sexual crosses in Aspergillus nidulans.

作者信息

Mason J R, Turner G

出版信息

Mol Gen Genet. 1975 Dec 30;143(1):93-9. doi: 10.1007/BF00269425.

Abstract

Three extranuclear mitochondrial mutations in Aspergillus nidulans, (oliA1), (camA1) and (cs67), were used as markers in sexual crosses to provide information on the frequencies of transmission and recombination of the mitochondrial genome. Any individual perithecium contained ascospores of only one extranuclear genotype. Using mono-, bi- and trifactorial crosses it was found that all three markers could be recovered from the progeny, although the transmission frequencies were different for each marker. This bias was present irrespective of the nuclear background or the presence of selective agents in the medium on which the cross was established. These findings enable a series of "transmission strength" to be established, as shown below:-- (camA1) greater than (cs67, camA1) greater than (+) = (cs67) greater than (oliA1, cs67) greater than (oliA1) greater than (oliA1, camA1). However, the numbers of recombinants isolated were so variable as to make this form of analysis unsuitable for mapping the mitochondrial genome.

摘要

构巢曲霉中的三个核外线粒体突变（oliA1）、（camA1）和（cs67）被用作有性杂交中的标记，以提供有关线粒体基因组传递和重组频率的信息。任何一个子囊果仅包含一种核外基因型的子囊孢子。通过单因子、双因子和三因子杂交发现，尽管每个标记的传递频率不同，但所有三个标记都可以从后代中恢复。无论核背景如何，也无论杂交所基于的培养基中是否存在选择剂，这种偏差都存在。这些发现使得能够建立一系列“传递强度”，如下所示：（camA1）大于（cs67，camA1）大于（+）=（cs67）大于（oliA1，cs67）大于（oliA1）大于（oliA1，camA1）。然而，分离出的重组体数量变化很大，以至于这种分析形式不适用于绘制线粒体基因组图谱。