菠萝酸性转化酶基因家族初步生物信息学及表达分析

酸性转化酶（acid invertase, AIN）在菠萝采后蔗糖降解过程中起着重要作用,基于菠萝全基因组数据库,预测菠萝AIN家族基因并进行生物信息学分析,解析其在采后菠萝不同贮藏温度下的表达变化情况,为阐明AIN基因在采后菠萝果实贮藏特性中的作用奠定基础。以水稻AIN家族基因为探针,在菠萝全基因组中鉴定到2个菠萝细胞壁酸性转化酶基因（cell wall acid invertase, CWIN）和2个液泡酸性转化酶基因（vacuolar acid invertase, VIN）,分别命名为AcCWIN1、AcCWIN2、AcVIN1、AcVIN2,设计编码区引物进行测序验证,并进行生物信息学分析。进化分析结果表明,AcCWIN1、AcCWIN2和AcVIN1、AcVIN2蛋白分别归于细胞壁酸性转化酶和液泡酸性转化酶2个进化支上,且均属于糖基水解酶家族GH32,基因结构、保守域和保守基序均一致。荧光定量分析结果表明,菠萝果肉中AcVIN1和AcVIN2在果实采后贮藏过程中表达量升高,且AcVIN1在发生黑心病的部位大量表达,而AcCWIN1和AcCWIN2在采后贮藏过程中表达量逐渐降低,且随着贮藏温度的升高其表达量降低,预示AcVIN1、AcVIN2较AcCWIN1、AcCWIN2在菠萝采后蔗糖降解和黑心病的发生方面发挥着更为重要的作用。

Identification and Expression Pattern Analysis of Acid Invertase Gene Family in Pineapple Fruit

Acid invertase plays an important role in the process of sucrose degradation of postharvestal pineapple. Based on the genome database of pineapple, AIN genes were identified and analyzed using the bioinformatics method, and the expression of AIN genes under different storage temperatures were analyzed, which would lay a foundation for clarifying the characteristics of AIN genes in postharvestal pineapple fruit storage. In this study, two cell wall invertase and two vacuolar invertase genes were identified in the pineapple genome using the AIN family gene of rice as the probe, named as AcCWIN1, AcCWIN2, and AcVIN1, AcVIN2 respectively, and verified sequences were further analyzed for bioinformatics information. The evolutionary analysis showed that AcCWIN1, AcCWIN2, and AcVIN1, AcVIN2 belonged to the two evolutionary branches of the cell wall acid invertase and vacuole acid invertase, respectively, which belonging to the glycohydrolase family GH32, and the gene structure, conserved domain and conserved motif were consistent. Fluorescence quantitative analysis showed that the expression of AcVIN1 and AcVIN2 increased during postharvest storage at room temperature, and AcVIN1 was abundantly expressed at the site of blackheart disease. The expression of AcCWIN1 and AcCWIN2 decreased gradually during postharvest storage at 10 ℃, 25 ℃ and 38 ℃, and were depressed with storage temperature increased, indicating that AcVIN1 and AcVIN2 played a more important role in sugar degradation and blackheart disease of pineapple than AcCWIN1 and AcCWIN2.