MEI4, a yeast gene required for meiotic recombination.
MEI4, a yeast gene required for meiotic recombination.
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作者：
T. Menees;G. Roeder
在寻找减数分裂基因转换缺陷的突变体中检测到MEI4基因座的突变体。Mei4突变体表现出减少的孢子形成并产生不能存活的孢子。孢子失活表型是由spo13突变拯救的，它导致细胞绕过减数分裂I分裂。MEI 4基因已通过重组缺陷的互补从酵母基因组文库中克隆出来，并已定位到染色体V gln 3附近。携带MEI4基因的缺失/插入突变的菌株不显示减数分裂诱导的基因转换，但正常的有丝分裂转换频率。在mei4株系中，减数分裂染色体间和染色体内的交换都被完全消除。mei4突变能够拯救spo 13和52菌株的孢子无活力表型（即，mei4spo13rad52突变体产生活孢子），表明MEI4在减数分裂重组途径中先于RAD 52起作用。
Mutants at the MEI4 locus were detected in a search for mutants defective in meiotic gene conversion. mei4 mutants exhibit decreased sporulation and produce inviable spores. The spore inviability phenotype is rescued by a spo13 mutation, which causes cells to bypass the meiosis I division. The MEI4 gene has been cloned from a yeast genomic library by complementation of the recombination defect and has been mapped to chromosome V near gln3. Strains carrying a deletion/insertion mutation of the MEI4 gene display no meiotically induced gene conversion but normal mitotic conversion frequencies. Both meiotic interchromosomal and intrachromosomal crossing over are completely abolished in mei4 strains. The mei4 mutation is able to rescue the spore-inviability phenotype of spo13 and 52 strains (i.e., mei4 spo13 rad52 mutants produce viable spores), indicating that MEI4 acts before RAD52 in the meiotic recombination pathway.