College of Horticulture, Shenyang Agricultural University, Shenyang, Liaoning, China.
Key Laboratory of Protected Horticulture of Education Ministry and Liaoning province, Shenyang, Liaoning, China.
PLoS One. 2020 May 14;15(5):e0232756. doi: 10.1371/journal.pone.0232756. eCollection 2020.
Mitogen-activated protein kinase (MAPK) is a form of serine/threonine protein kinase that activated by extracellular stimulation acting through the MAPK cascade (MAPKKK-MAPKK-MAPK). The MAPK cascade gene family, an important family of protein kinases, plays a vital role in responding to various stresses and hormone signal transduction processes in plants. In this study, we identified 14 CmMAPKs, 6 CmMAPKKs and 64 CmMAPKKKs in melon genome. Based on structural characteristics and a comparison of phylogenetic relationships of MAPK gene families from Arabidopsis, cucumber and watermelon, CmMAPKs and CmMAPKKs were categorized into 4 groups, and CmMAPKKKs were categorized into 3 groups. Furthermore, chromosome location revealed an unevenly distribution on chromosomes of MAPK cascade genes in melon, respectively. Eventually, qRT-PCR analysis showed that all 14 CmMAPKs had different expression patterns under drought, salt, salicylic acid (SA), methyl jasmonate (MeJA), red light (RL), and Podosphaera xanthii (P. xanthii) treatments. Overall, the expression levels of CmMAPK3 and CmMAPK7 under different treatments were higher than those in control. Our study provides an important basis for future functional verification of MAPK genes in regulating responses to stress and signal substance in melon.
丝裂原活化蛋白激酶（MAPK）是一种丝氨酸/苏氨酸蛋白激酶，通过 MAPK 级联（MAPKKK-MAPKK-MAPK）激活，该级联由细胞外刺激作用。MAPK 级联基因家族作为重要的蛋白激酶家族，在植物响应各种胁迫和激素信号转导过程中发挥着至关重要的作用。本研究在甜瓜基因组中鉴定到 14 个 CmMAPKs、6 个 CmMAPKKs 和 64 个 CmMAPKKKs。基于结构特征和拟南芥、黄瓜和西瓜 MAPK 基因家族的系统发育关系比较，将 CmMAPKs 和 CmMAPKKs 分为 4 组，将 CmMAPKKKs 分为 3 组。此外，MAPK 级联基因在甜瓜染色体上的位置显示出不均匀的分布。最后，qRT-PCR 分析表明，14 个 CmMAPKs 在干旱、盐、水杨酸（SA）、茉莉酸甲酯（MeJA）、红光（RL）和蔓枯病菌（P. xanthii）处理下的表达模式均不同。总体而言，不同处理下 CmMAPK3 和 CmMAPK7 的表达水平均高于对照。本研究为今后甜瓜 MAPK 基因在调节对胁迫和信号物质的响应中的功能验证提供了重要依据。
