title: High expression of PP2A-Aα is associated with diapause induction during the photoperiod-sensitive stage of the cotton bollworm, Helicoverpa armigera.
abstract: Protein phosphatase 2A (PP2A) is a major serine-threonine protein phosphatase which regulates metabolism, transcription, RNA splicing, translation, differentiation, cell cycle, oncogenic transformation and signal transduction. PP2A-Aα, an isoform of PP2A-A, is a structural subunit of the PP2A complex. We identified the photoperiod-sensitive stage for pupal diapause induction to be from the fifth instar to the early sixth instar larvae in the cotton bollworm, Helicoverpa armigera. PP2A-Aα cDNA from brains of diapause-destined fifth instar larvae was obtained by suppressive subtractive hybridization using nondiapause-destined larval brains as a control. Developmental expression of PP2A-Aα mRNA during the photoperiod-sensitive stage was higher in brains of diapause-destined larvae, and the PP2A-Aα protein showed a similar expression pattern as the mRNA. When larvae were transferred from diapause-inducing short days to long days during the diapause-sensitive stage, both PP2A-Aα mRNA and protein decreased significantly, and diapause incidence was also reduced. Thus, high PP2A-Aα expression during the diapause-sensitive stage may play a crucial role in photoperiodic induction of diapause, suggesting that it may be a new player involved in the molecular mechanism for diapause induction.
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Tian
authors.forename: Wei-Hua
authors.initials: WH
authors.lastname: Xu
mesh_terms: D000818:Animals; D018507:Gene Expression Regulation, Developmental / Q000528:radiation effects*; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D009036:Moths / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000528:radiation effects; D017440:Photoperiod; D054648:Protein Phosphatase 2 / Q000235:genetics* / Q000378:metabolism; D011679:Pupa / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000528:radiation effects
chemical_list: D019476:Insect Proteins; D054648:Protein Phosphatase 2