Abstract: 【Aim】 This study aims to clone the c-Jun N-terminal kinase (JNK) gene and to analyze the gene sequence and mRNA expression profiles in Helicoverpa armigera, so as to explore the function of JNK gene in the growth and development of the moth and its responses to UV-A stress. 【Methods】 The full-length cDNA of the JNK gene of H. armigera was cloned and identified using RT-PCR and RACE technique. The putative amino acid sequence of the JNK gene was analyzed by bioinformatics methods. The expression levels of the JNK gene in different developmental stages (egg, 1st-6th instar larva, pupa, female and male adult), adult tissues (head with antennae and compound eyes removed, thorax, abdomen, antenna, compound eye, legs, wing, midgut and ovary) and female adults exposed to UV-A for various time periods (0, 30, 60, 90, 120 and 150 min) were detected by real-time quantitative PCR (RT-qPCR). 【Results】 A JNK gene was cloned from H. armigera, and named HaJNK (GenBank accession no.: MH719009), which is 2 431 bp in length and contains an open reading frame (ORF) of 1 191 bp, encoding 396 amino acid residues. The putative protein is 45.01 kD with an isoelectric point (pI) of 6.35, and has no transmembrane region and signal peptide. The phylogenic tree indicated that HaJNK shares a high homology with JNKs from other insect species. Developmental stage-specific mRNA expression profiling showed that HaJNK had the highest expression levels in the egg stage. Tissue-specific mRNA expression profiling showed that HaJNK was specifically expressed in the compound eye, thorax and ovary of adult. The mRNA expression of HaJNK in female adults was induced by UV-A stress, increasing firstly and then decreasing with the increase of exposure time, and reached the highest expression level at 60 min post exposure to UV-A. 【Conclusion】 This study indicates that the expression level of HaJNK varies at different developmental stages, adult tissues and female adults of H. armigera exposed to UV-A for different time, suggesting that HaJNK may play an important role in the response to UV-A stress.

Key words: Helicoverpa armigera, c-Jun N-terminal kinase, gene cloning, expression analysis, UV-A stress