Unconventional translation initiation factor EIF2A is required for Drosophila spermatogenesis.
CG7414
EIF2A
individualization
spermatogenesis
translational regulation
unconventional protein synthesis
unconventional translation initiation factor
Journal
Developmental dynamics : an official publication of the American Association of Anatomists
ISSN: 1097-0177
Titre abrégé: Dev Dyn
Pays: United States
ID NLM: 9201927
Informations de publication
Date de publication:
02 2022
02 2022
Historique:
revised:
23
06
2021
received:
17
04
2021
accepted:
09
07
2021
pubmed:
20
7
2021
medline:
8
4
2022
entrez:
19
7
2021
Statut:
ppublish
Résumé
EIF2A is an unconventional translation factor required for initiation of protein synthesis from non-AUG codons from a variety of transcripts, including oncogenes and stress related transcripts in mammalian cells. Its function in multicellular organisms has not been reported. Here, we identify and characterize mutant alleles of the CG7414 gene, which encodes the Drosophila EIF2A ortholog. We identified that CG7414 undergoes sex-specific splicing that regulates its male-specific expression. We characterized a Mi{Mic} transposon insertion that disrupts the coding regions of all predicted isoforms and is a likely null allele, and a PBac transposon insertion into an intron, which is a hypomorph. The Mi{Mic} allele is homozygous lethal, while the viable progeny from the hypomorphic PiggyBac allele are male sterile and female fertile. In dEIF2A mutant flies, sperm failed to individualize due to defects in F-actin cones and failure to form and maintain cystic bulges, ultimately leading to sterility. These results demonstrate that EIF2A is essential in a multicellular organism, both for normal development and spermatogenesis, and provide an entrée into the elucidation of the role of EIF2A and unconventional translation in vivo.
Sections du résumé
BACKGROUND
EIF2A is an unconventional translation factor required for initiation of protein synthesis from non-AUG codons from a variety of transcripts, including oncogenes and stress related transcripts in mammalian cells. Its function in multicellular organisms has not been reported.
RESULTS
Here, we identify and characterize mutant alleles of the CG7414 gene, which encodes the Drosophila EIF2A ortholog. We identified that CG7414 undergoes sex-specific splicing that regulates its male-specific expression. We characterized a Mi{Mic} transposon insertion that disrupts the coding regions of all predicted isoforms and is a likely null allele, and a PBac transposon insertion into an intron, which is a hypomorph. The Mi{Mic} allele is homozygous lethal, while the viable progeny from the hypomorphic PiggyBac allele are male sterile and female fertile. In dEIF2A mutant flies, sperm failed to individualize due to defects in F-actin cones and failure to form and maintain cystic bulges, ultimately leading to sterility.
CONCLUSIONS
These results demonstrate that EIF2A is essential in a multicellular organism, both for normal development and spermatogenesis, and provide an entrée into the elucidation of the role of EIF2A and unconventional translation in vivo.
Substances chimiques
Drosophila Proteins
0
Peptide Initiation Factors
0
Types de publication
Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
377-389Subventions
Organisme : NIA NIH HHS
ID : R01 AG063907
Pays : United States
Organisme : NIGMS NIH HHS
ID : T32 GM096911
Pays : United States
Informations de copyright
© 2021 American Association for Anatomy.
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