PMID- 28761009
OWN - NLM
STAT- MEDLINE
DCOM- 20180423
LR  - 20190923
IS  - 0973-7731 (Electronic)
IS  - 0022-1333 (Linking)
VI  - 96
IP  - 3
DP  - 2017 Jul
TI  - Ascus dysgenesis in hybrid crosses of Neurospora and Sordaria (Sordariaceae).
PG  - 457-463
AB  - When two lineages derived from a common ancestor become reproductively isolated 
      (e.g. Neurospora crassa and N. tetrasperma), genes that have undergone mutation 
      and adaptive evolution in one lineage can potentially become dysfunctional when 
      transferred into the other, since other genes have undergone mutation and 
      evolution in the second lineage, and the derived alleles were never 'tested' 
      together before hybrid formation. Bateson (1909), Dobzhansky (1936), and Muller 
      (1942) recognized that incompatibility between the derived alleles could 
      potentially make the hybrid lethal, sterile, or display some other detriment. 
      Alternatively, the detrimental effects seen in crosses with the hybrids may 
      result from the silencing of ascus-development genes by meiotic silencing by 
      unpaired DNA (MSUD). Aberrant transcripts from genes improperly paired in meiosis 
      are processed into single-stranded MSUD-associated small interfering RNA 
      (masiRNA), which is used to degrade complementary mRNA. Recently, backcrosses of 
      N. crassa / N. tetrasperma hybrid translocation strains with wild-type N. 
      tetrasperma were found to elicit novel ascus dysgenesis phenotypes. One was a 
      transmission ratio distortion that apparently disfavoured the homokaryotic 
      ascospores formed following alternate segregation. Another was the production of 
      heterokaryotic ascospores in eight-spored asci. Lewis (1969) also had reported 
      sighting rare eight-spored asci with heterokaryotic ascospores in interspecific 
      crosses in Sordaria, a related genus. Ordinarily, in both Neurospora and 
      Sordaria, the ascospores are partitioned at the eight-nucleus stage, and 
      ascospores in eight-spored asci are initially uninucleate. Evidently, in hybrid 
      crosses of the family Sordariaceae, ascospore partitioning can be delayed until 
      after one or more mitoses following the postmeiotic mitosis.
FAU - Kasbekar, Durgadas P
AU  - Kasbekar DP
AD  - Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500 001, India. 
      kas@cdfd.org.in.
LA  - eng
PT  - Journal Article
PT  - Review
PL  - India
TA  - J Genet
JT  - Journal of genetics
JID - 2985113R
SB  - IM
MH  - Crosses, Genetic
MH  - Gene Expression Regulation, Fungal
MH  - Genes, Fungal/genetics
MH  - Hybridization, Genetic
MH  - *Mutation
MH  - Neurospora/*genetics
MH  - Phenotype
MH  - Sordariales/*genetics
MH  - Spores, Fungal/*genetics
MH  - Translocation, Genetic
EDAT- 2017/08/02 06:00
MHDA- 2018/04/24 06:00
CRDT- 2017/08/02 06:00
PHST- 2017/08/02 06:00 [entrez]
PHST- 2017/08/02 06:00 [pubmed]
PHST- 2018/04/24 06:00 [medline]
AID - 10.1007/s12041-017-0765-z [doi]
PST - ppublish
SO  - J Genet. 2017 Jul;96(3):457-463. doi: 10.1007/s12041-017-0765-z.