Abstract:

The aim of this study was to explore the mechanisms of N-acetylglucosaminyltransferase
gene（CmGnT）in melon under abiotic stresses. Primers were designed according to cDNA sequence of
melon，and CmGnT was cloned by using RT-PCR technique. The full-length cDNA of CmGnT was 2 193
bp，and the open reading frame（ORF）was 1 179 bp，encoding 392 amino acids. The molecular weight of
CmGnT protein was about 46 kD，and the theoretical isoelectric point（pI）was 7.93. Protein structure analysis showed that CmGnT contained the β-1,4-N-acetylglucosaminyltransferase domain ， which
belonged to the glycosyltransferases 17 family. The protein had 1 strong transmembrane helices.
Phylogenetic analysis showed that CmGnT and CsGnT（accession number：XP_004135275.1）had the
closest genetic relationship，and the homology was 99.74%. Homology with watermelon was 97.70%.
qRT-PCR analysis showed that the expressions of CmGnT in leaf were significantly up-regulated under
NaCl，PEG，H2O2 and ABA stresses，which indicated that CmGnT was induced by abiotic stresses. The
results suggested that this gene in melon played an important role in response to abiotic stresses.

Key words: melo, N-acetylglucosaminyltransferase, gene clone, gene expression, abiotic stresses