Plant and Crop Sciences Division, School of Biosciences , University of Nottingham , Sutton Bonington Campus , Loughborough , LE12 5RD , United Kingdom.
J Agric Food Chem. 2019 May 8;67(18):5204-5211. doi: 10.1021/acs.jafc.9b00641. Epub 2019 Apr 26.
Texture attributes such as firmness and lignification are important for fruit quality. Lignification has been widely studied in model plants and energy crops, but fruit lignification has rarely been investigated, despite having an adverse effect on fruit quality and consumer preference. Chilling-induced loquat fruit lignification that occurs after harvest can be alleviated by heat treatment (HT) applied prior to low temperature storage. Enzyme activity assay showed that HT treatment could retard the low temperature-induced increase in cinnamyl alcohol dehydrogenase (CAD) activity. Transcript analysis and substrate activity assays of recombinant CAD proteins highlighted the key role of EjCAD5 in chilling-induced lignin biosynthesis. A novel homeobox-leucine zipper protein ( EjHAT1) was identified as a negative regulator of EjCAD5. Therefore, the effect of HT treatment on lignification may be partially due to the suppression of the EjCAD5 promoter activity by EjHAT1.
质地属性如硬度和木质化对果实品质很重要。木质化在模式植物和能源作物中已得到广泛研究，但果实木质化却很少被研究，尽管它对果实品质和消费者偏好有不利影响。低温贮藏前进行热处理（HT）可以缓解冷藏后枇杷果实的木质化。酶活性测定表明，HT 处理可延缓低温诱导的肉桂醇脱氢酶（CAD）活性的增加。EjCAD5 在低温诱导木质素生物合成中起关键作用。鉴定出一个新的同源盒亮氨酸拉链蛋白（EjHAT1）是 EjCAD5 的负调控因子。因此，HT 处理对木质化的影响可能部分是由于 EjHAT1 抑制了 EjCAD5 启动子活性。
