Transmethylation reaction is essential for Sarcophaga lectin gene activation.
Incubation of Sarcophaga fat bodies in buffered insect saline resulted in simultaneous activation of multiple defense protein genes [Sugiyama, H. and Natori, S. (1991) Eur. J. Biochem. 200, 495-500]. In this study, we demonstrated that the addition of both adenosine and homocysteine thiolactone to this medium abolished activation of these defense protein genes. As S-adenosyl-homocysteine, a potent inhibitor of the transmethylation reaction, is produced in the fat body under these conditions, methylation of a certain fat body protein seems to be a prerequisite for the selective activation of insect defense protein genes. Activation of the HSP70 gene was not interfered with S-adenosyl-homocysteine.
Sugiyama
H
H
Faculty of Pharmaceutical Science, University of Tokyo.
Natori
S
S
D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D004175:Diptera / Q000235:genetics*; D005216:Fat Body / Q000378:metabolism; D005786:Gene Expression Regulation; D037102:Lectins / Q000235:genetics*; D008745:Methylation; D008969:Molecular Sequence Data; D012435:S-Adenosylhomocysteine / Q000378:metabolism; D015533:Transcriptional Activation
D017931:DNA Primers; D037102:Lectins; D012435:S-Adenosylhomocysteine