RRC ID 28991
Author Osherov N, Wang N, Loomis WF.
Title Precocious sporulation and developmental lethality in yelA null mutants of Dictyostelium.
Journal Dev Genet
Abstract A novel developmental gene, yelA, has been found that plays as essential role in regulating terminal differentiation of Dictyostelium discoideum. Strains in which yelA is disrupted by plasmid insertion are arrested at the tight mound stage but accumulate the bright yellow pigment characteristic of mature sori. Although these mutant strains do not form fruiting bodies, many of the cells encapsulate within the mounds. Sporulation occurs about 6 hours earlier in yelA- cells than in wild-type cells, accompanied by precocious expression of a prespore gene, spiA. However, the spores are defective and lose viability over a period of several hours. Unencapsulated cells also die unless they are dissociated from the mounds and shaken in suspension. The yelA gene was isolated by plasmid rescue and found to encode a protein of 102 kDa in which the N-terminal sequence shows significant similarity to domains found in the eIF-4G subunits of the translational initiation complex eIF-4F. In wild-type cells yelA mRNA first accumulates at 8 hours of development and is maintained in both prespore and prestalk cells until culmination when it is found only is stalk cells. Mutations in yelA can partially suppress the block to sporulation in mutant strains in which either of the prestalk genes tagB or tagC is disrupted such that an encapsulation signal is not produced. It appears that premature encapsulation is normally inhibited by YelA until a signal is received from prestalk cells during culmination.
Volume 20(4)
Pages 307-19
Published 1997-1-1
DOI 10.1002/(SICI)1520-6408(1997)20:4<307::AID-DVG2>3.0.CO;2-B
PII 10.1002/(SICI)1520-6408(1997)20:4<307::AID-DVG2>3.0.CO;2-B
PMID 9254905
MeSH Amino Acid Sequence Animals Cloning, Molecular Cyclic AMP / physiology Cyclic AMP-Dependent Protein Kinases / physiology Dictyostelium / genetics* Dictyostelium / physiology Fungal Proteins / genetics Fungal Proteins / physiology* Gene Deletion Gene Expression Regulation, Developmental* Gene Expression Regulation, Fungal* Genes, Lethal Genetic Complementation Test Molecular Sequence Data Protozoan Proteins / genetics Protozoan Proteins / physiology* Recombinant Fusion Proteins / physiology Sequence Alignment Sequence Homology, Amino Acid Signal Transduction Spores, Fungal
Times Cited 9
Cellular slime molds S00330