Cloning and Response to Environmental Cues of BnCOP9 from Brassica napus

Plant COP9(Constitutively photomorphogenic 9)signalosome(CSN)is a multi-subunit complex in which CSN8 is an obligatory subunit.To clone CSN8 and investigate its response to environmental cues in oilseed rape,a full length cDNA of Brassica napus CSN8(BnCOP9)was isolated from the line Zhongshuang9 by homology cloning approach.Sequence analysis showed that BnCOP9 contains a PCI domain in the central region and 197 amino acids exhibiting a 92% identity with Arabidopsis CSN8(AtCOP9).Quantitative RT-PCR analysis showed that BnCOP9 expression were promptly activated by Sclerotinia sclerotiorum,wound treatment and MeJA,while suppressed by Benzothiadiazole,suggesting that BnCOP9 is in response to environmental stresses and play a role in crossing-talk of SA-and JA-mediated signaling and the molecular network of oilseed rape response against both S.sclerotioru and wound.These results provide a cue to study a role of the CSN complex in defense responses in oilseed rape.