Perspective - Journal of Pediatric Neurological Disorders (2022) Volume 5, Issue 3

Short Notes on Meiotic and Mitotic Phenotypes Conferred by the blm1-1 Mutation in Saccharomyces cerevisiae

Opeyemi Oluwasanmi Adeloye*

Rosad Neurodegenerative Research Institute Jos, University of Medical Science Teaching Hospital, Ondo

*Corresponding Author:
Opeyemi Oluwasanmi Adeloye Rosad Neurodegenerative Research Institute Jos, University of Medical Science Teaching Hospital, Ondo E-mail:

Received: 02-Jun-2022, Manuscript No. pnn-22-421013; Editor assigned: 06-Jun-2022, PreQC No. pnn-22- 421013(PQ); Reviewed: 20-Jun-2022, QC No. pnn-22-421013; Revised: 23-Jun-2022, Manuscript No. pnn-22- 421013(R); Published: 30-Jun-2022, DOI: 10.37532/pnn.2022.5(3).56-57


Oxidative injury will cause variety of diseases, and may be fatal. The blm1-1 mutation of yeast confers hyper susceptibility to deadly effects of the oxidative, antineoplastic and antimitotic agent, bleomycin. For this report, additional defects given by the mutation in meiosis and cellular division were investigated. The viability of spores created throughout meiosis by homozygous traditional BLM1/BLM1, heterozygous BLM1/blm1-1, and homozygous mutant blm1-1/blm1-1 diploid strains was studied and compared. Close to half a mile of the tetrads derived from homozygous blm1-1/blm1-1 mutant diploid cells solely created one or two viable spores. In distinction, only 1 digit among all BLM1/ BLM1 and BLM1/blm1-1 tetrads solely created one or 2 viable spores. Rather, ninety four of BLM1/BLM1 tetrads and 100% of BLM1/blm1-1 tetrads created ace with four or 3 viable spores. Thus, a minimum of one copy of the BLM1 factor is crucial for the production of 4 viable spores once meiosis.


bleomycins • phleomycins • aerophilic injury • microorganism


The structures of bleomycins and structurally-related phleomycin are shown in Figure one. These low mass compounds cause single- and double-stranded breaks in DNA and injury to fungal cell walls. They bind to DNA generate free radicals in an oxygen-dependent, metal dependent reaction. Bleomycins and phleomycin are radiomimetic therein they turn out effects similar to those ascertained once exposure of DNA to radiation. As a result, the medicine is employed as tools in studies of aerophilic injury to cells. To achieve data regarding however cells respond to aerophilic injury[1-2]. We tend to isolate a series of mutants in yeast that confer hypersensitivity to killing by the bleomycins and phleomycins. One in all these mutants contained the recessive blm1-1 mutation. Additional defects given by blm1-1 were investigated for this report. We tend to additionally describe the biological research and isolation of the MSH4 factor, essential for wild-type reproductive structure viability in S.cerevisiae. The Msh4 macromolecule may be a homolog of the Mutes DNA twin repair macromolecule in microorganism. Tetrad analyses indicated that the BLM1 factor is crucial for the assembly of four viable spores once meiosis and mitotic analyses indicated BLM1 is crucial mitotic growth [3].


The viability of spores from homozygous blm1-1/blm1-1 mutant strains was compared thereto of spores from BLM1/BLM1 homozygous traditional strains and heterozygous BLM1/blm1-1 strains. The homozygous traditional diploid was created by crossing 2 wildtype haploid sergeants, CM1457-79A and CM1457-79B . The heterozygous diploid was created by crossing a wild-type haploid, CM1457-79A, to a mutant haploid, CM1457-79C. The homozygous mutant diploid was created by crossing 2 mutant haploids, CM1457- 79C and CM1457-79D. Every diploid was sporulated, and the tetrads obtained from every sporulated diploid were cleft [4]. The viability of the spores in every digit is tabulated in Table two. 94 % of the tetrads from the BLM1/BLM1 diploid and 100% of the tetrads from the BLM1/blm1-1 diploids created four or 3 viable spores. In distinction, no tetrads from blm1-1/blm1-1 cells created ash with four viable spores, and solely thirteen of the tetrads created 3 viable spores. One- or two-spore viability was predominant. Thus, within the presence of 1 or 2 copies of the BLM1 factor (as in homozygous or heterozygous diploids), tetrads seem capable of finishing meiosis and manufacturing four viable spores. However, within the absence of the BLM1 factor, cells seem unable to finish meiosis and turn out four viable spores. These results indicate that the BLM1 factor is crucial for the viability of all four spores after meiosis, which the blm1-1 mutation confers a deficiency in meiosis since the homozygous mutant cells are unable to provide four viable spores [5].



Conflict of Interests



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