关键词: 苹果, NBS-LRR, 基因表达, 水杨酸, 茉莉酸甲酯, ACC, Botryosphaeria dothidea

Abstract: NBS-LRR proteins are one protein family which contains Nucleotide-binding site（NBS）and leucine-rich repeat（LRR），and play an important role in defending plants from various pathogens. Anew NBS-LRR gene was identified from‘Gala’apple and named MdNBS-LRR1（JX126858）. The fullcDNA was 3 116 bp in length with an open reading frame（ORF）of 2 826 bp and encoded a protein of 941amino acids. The putative amino acid sequence contains an NB-ARC domain. The BLAST analysis exhibited high identity（60%）to NBS-LRR resistant protein（ACM89637）from Glycine max. Real time quantitative PCR analysis showed that the expression of MdNBS-LRR1 was observed in all tissues tested here including young leaves，shoot，functional leaves，bud，bark and flower，and the highest expression level was found in younger leaves. The expression of MdNBS-LRR1 was up-regulated by infection with Botryosphaeria dothide and reached the peak value at 24 d（10.6-fold higher than that in control）after inoculation. In addition，SA，MeJA and ACC could induce the expression of MdNBS-LRR1 gene in leaves，indicating that MdNBS-LRR1 could be regulated by the disease-resistant related signaling pathway.

Key words: Malus ×, domestica, NBS-LRR, gene expression, salicylic acid, methyl jasmonate, ACC, Botryosphaeria dothidea