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Title: Isolation of rfk-2UV, a mutation that blocks spore killing by Neurospora Spore killer-3
Neurospora Spore killer-3 (Sk-3) is a selfish genetic element that kills spores to achieve gene drive. Here, we describe the isolation and mapping of rfk-2UV, a mutation that disrupts spore killing. The rfk-2UV mutation is located 15.6 cM from mus-52 on Chromosome III. The significance of this discovery with respect to Sk-3 evolution is discussed  more » « less
Award ID(s):
2005295
PAR ID:
10342590
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
microPublication biology
ISSN:
2578-9430
Page Range / eLocation ID:
micropub-biology-000604
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. (, ISU ReD: Research and eData)
    Meiotic drive describes a process in which selfish alleles are recovered in more than half of a progeny generation. It is a type of gene drive and it has been discovered in strains of Neurospora, a filamentous fungus, through its spore killing mechanism. One of the most studied meiotic drive elements within N. crassa is Spore killer-3 (Sk-3). Previous studies have indicated that there is a genomic region within Sk-3 that encodes resistance to spore killing and another that encodes an element that is required for spore killing. Sk-3’s resistance gene, rsk, has been identified. However, the exact region that mediates Sk-3’s spore killing mechanism is currently unknown. In a previous study, it was found that a mutation called rfk-2UV disrupts spore killing by Sk-3. To better understand the region of Chromosome III in which rfk-2UV is located (its exact location is unknown), I constructed a deletion vector to replace a DNA interval (v374) with a hygromycin resistance gene marker (hph). Transformants were crossed to produce offspring, and offspring were tested to determine if they possess the ability to kill ascospores. These findings will contribute to future efforts to determine the molecular nature of rfk-2UV and why this mutation disrupts the ability of Sk-3 to kill spores. 
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  2. ; (, bioRxiv)
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  3. (, ISU ReD: Research and eData)
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  4. (, ISU ReD: Research and eData)
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  5. (, ISU ReD: Research and eData)
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