Regional and developmental expression of Epm2a gene and its evolutionary conservation.
Lafora's disease, an autosomal recessive progressive myoclonus epilepsy, is caused by mutations in the EPM2A gene encoding a dual-specificity phosphatase (DSP) named laforin. Here, we analyzed the developmental and regional expression of murine Epm2a and discussed its evolutionary conservation. A phylogenetic analysis indicated that laforin is evolutionarily distant from other DSPs. Southern zoo blot analysis suggested that conservation of Epm2a gene is limited to mammals. Laforin orthologs (human, mouse, and rat) display more than 94% similarity. All missense mutations known in Lafora disease patients affect conserved residues, suggesting that they may be essential for laforin's function. Epm2a is expressed widely in various organs but not homogeneously in brain. The levels of Epm2a transcripts in mice brains increase postnatally, attaining its highest level in adults. The most intense signal was detected in the cerebellum, hippocampus, cerebral cortex, and the olfactory bulb. Our results suggest that Epm2a is functionally conserved in mammals and is involved in growth and maturation of neural networks.
Ganesh
S
S
Laboratory for Neurogenetics, RIKEN Brain Science Institute, Wako-shi, Saitama, 351-0198, Japan.
Agarwala
K L
KL
Amano
K
K
Suzuki
T
T
Delgado-Escueta
A V
AV
Yamakawa
K
K
D000375:Aging; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001921:Brain / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D017124:Conserved Sequence; D054637:Dual-Specificity Phosphatases; D005314:Embryonic and Fetal Development; D019143:Evolution, Molecular; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D009928:Organ Specificity; D010802:Phylogeny; D017027:Protein Tyrosine Phosphatases / Q000737:chemistry* / Q000235:genetics*; D054558:Protein Tyrosine Phosphatases, Non-Receptor; D051381:Rats; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014714:Vertebrates
D054637:Dual-Specificity Phosphatases; C491989:Epm2a protein, mouse; C491988:Epm2a protein, rat; D017027:Protein Tyrosine Phosphatases; D054558:Protein Tyrosine Phosphatases, Non-Receptor; C114990:EPM2A protein, human