Nagasowjanya, T. and Raj, K.B. and Sreethi Reddy, K. and Kasbekar, D.P. (2013) An apparent increase in meiotic silencing strength in crosses involving inbred Neurospora crassa strains. Fungal Genetics and Biology, 56. pp. 158-162. ISSN 1087-1845

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Abstract

Meiotic silencing by unpaired DNA is a presumed RNAi-mediated elimination of the transcripts of any gene that is not properly paired with a homolog in meiosis. Wild-isolated strains of Neurospora crassa can be classified into three types based on the apparent strength of meiotic silencing of the bml (β-tubulin) and mei-3 genes in crosses of the wild strains with the tester strains ::Bml(r) and ::mei-3. Crosses with "OR" and "Sad" type wild-isolates, respectively, did or did not silence both the genes, whereas crosses with the "Esm" type silenced bml, but not mei-3(+). Presumably, bml is more sensitive to silencing than mei-3, and silencing is strongest in crosses with the OR type, weakest (or non-evident) in crosses with the Sad type, and of intermediate strength in crosses with Esm type. Now, while constructing recombinant inbred lines from the Sad type wild strains Bichpuri-1 a and Spurger-3 A, we found that although crosses of Bichpuri-1 a and Spurger-3 A, and of most of their f1 progeny, with the ::Bml(r) and ::mei-3 testers were consistently and reproducibly Sad type, those of later generation strains of each line could show Sad, Esm, or a variably expressive Sad/Esm type. Since any genotype found in a later generation is, in principle, obtainable in the f1, the observed transition from an apparently stable Sad phenotype to an apparently unstable Sad/Esm phenotype appears not to be due to genotype differences between the generations. Therefore, the Sad versus Esm difference may have a genotype-independent basis. Copyright © 2013 Elsevier Inc. All rights reserved.

Item Type:	Article
Depositing User:	Users 2 not found.
Date Deposited:	15 Sep 2015 06:36
Last Modified:	15 Sep 2015 06:36
URI:	http://cdfd.sciencecentral.in/id/eprint/513

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