不同丝瓜品种褐变相关基因的表达分析

以7种不同丝瓜品种为试验材料,对采后丝瓜果实进行褐变鉴定,测定多酚氧化酶(PPO)活性、过氧化物酶(POD)活性及相关基因的表达量。结果表明:"苏丝3号""苏丝6号""苏丝7号"属于抗褐变品种;"苏丝4号""苏丝5号""苏丝10号"属于耐褐变品种;"苏丝8号"属于严重褐变。从褐变酶POD和PPO变化来看,"苏丝8号"POD活性高达456.7 U·mg-1,抗褐变品种"苏丝3号""苏丝6号""苏丝7号"POD活性均在250 U·mg-1。"苏丝8号"PPO活性为68.2 U·mg-1,"苏丝3号"PPO活性最小,低至25.2 U·mg-1。从褐变基因的变化来看,"苏丝8号"在LcPOD家族基因表达中均高于对照"苏丝3号",其中LcPOD3基因表达量高达5.23,是对照的5倍以上,其它的丝瓜品种LcPOD3基因变化不显著。褐变品种"苏丝8号"在LcPPO基因家族中上调显著,表明"苏丝8号"果实褐变时促进LcPPO基因家族的表达,从而转录翻译成PPO加快果实的褐变。与对照相比,丝瓜褐变基因LCWRKY在"苏丝8号"中上调显著,表明其参与了丝瓜果实采后褐变。其它丝瓜品种LCWRKY上调不显著。

Gene Expression Related to Brown in Different Luffa Varieties

The different cultivars of Luffa were used as the research materials,to identificate postharvest Luffa fruit browning,activity of PPO,POD and relate gene express were analyzed.The results showed that ‘susi3’‘susi6’‘susi7’were brown resistant varieties,‘susi4’‘susi5’‘susi10’ were brown resistant varieties,while ‘susi8’ belonged to severe browning variety.According to the change of POD and PPO,the activity of POD of ‘susi8’ was 456.7 U·mg-1 prot,and that of resistant varieties ‘susi3’‘susi6’‘susi7’ were 250 U·mg-1.PPO activity of ‘susi8’ was 68.2 U·mg-1,and that of ‘susi3’ was the lowest,which was 25.2 U·mg-1 prot.According to the change of brown gene,the expression of LcPOD family gene in ‘susi8’ was higher than that of CK.The expression of LcPOD3 gene was 5.23,more than five times that of CK.There was no significant change in LcPOD3 gene in other Luffa varieties.The brown ‘susi8’ was significantly up-regulated in the LcPPO gene family.It showed that the expression of LcPPO gene family was enhanced during fruit of Luffa browning of ‘susi8’,and the expression of Lc PPO gene family was translated into PPO enzyme to accelerate fruit browning. Compared with CK,the brown gene LCWRKY of Luffa was significantly up-regulated in‘susi8’. It indicated that it was involved in postharvest browning of Luffa fruit. There was no significantly upregulated in brown gene LCWRKY of others.