Abstract：
BACKGROUND: Low-temperature severely limits the growth and development of Camellia oleifera (C. oleifera). The mitogen-activated protein kinase (MAPK) cascade plays a key role in the response to cold stress.
RESULTS: Our study aims to identify MAPK cascade genes in C. oleifera and reveal their roles in response to cold stress. In our study, we systematically identified and analyzed the MAPK cascade gene families of C. oleifera, including their physical and chemical properties, conserved motifs, and multiple sequence alignments. In addition, we characterized the interacting networks of MAPKK kinase (MAPKKK)-MAPK kinase (MAPKK)-MAPK in C. oleifera. The molecular mechanism of cold stress resistance of MAPK cascade genes in wild C. oleifera was analyzed by differential gene expression and real-time quantitative reverse transcription-PCR (qRT-PCR).
CONCLUSIONS: In this study, 21 MAPKs, 4 MAPKKs and 55 MAPKKKs genes were identified in the leaf transcriptome of C. oleifera. According to the phylogenetic results, MAPKs were divided into 4 groups (A, B, C and D), MAPKKs were divided into 3 groups (A, B and D), and MAPKKKs were divided into 2 groups (MEKK and Raf). Motif analysis showed that the motifs in each subfamily were conserved, and most of the motifs in the same subfamily were basically the same. The protein interaction network based on Arabidopsis thaliana (A. thaliana) homologs revealed that MAPK, MAPKK, and MAPKKK genes were widely involved in C. oleifera growth and development and in responses to biotic and abiotic stresses. Gene expression analysis revealed that the CoMAPKKK5/CoMAPKKK43/CoMAPKKK49-CoMAPKK4-CoMAPK8 module may play a key role in the cold stress resistance of wild C. oleifera at a high-elevation site in Lu Mountain (LSG). This study can facilitate the mining and utilization of genetic resources of C. oleifera with low-temperature tolerance.
RESULTS: Our study aims to identify MAPK cascade genes in C. oleifera and reveal their roles in response to cold stress. In our study, we systematically identified and analyzed the MAPK cascade gene families of C. oleifera, including their physical and chemical properties, conserved motifs, and multiple sequence alignments. In addition, we characterized the interacting networks of MAPKK kinase (MAPKKK)-MAPK kinase (MAPKK)-MAPK in C. oleifera. The molecular mechanism of cold stress resistance of MAPK cascade genes in wild C. oleifera was analyzed by differential gene expression and real-time quantitative reverse transcription-PCR (qRT-PCR).
CONCLUSIONS: In this study, 21 MAPKs, 4 MAPKKs and 55 MAPKKKs genes were identified in the leaf transcriptome of C. oleifera. According to the phylogenetic results, MAPKs were divided into 4 groups (A, B, C and D), MAPKKs were divided into 3 groups (A, B and D), and MAPKKKs were divided into 2 groups (MEKK and Raf). Motif analysis showed that the motifs in each subfamily were conserved, and most of the motifs in the same subfamily were basically the same. The protein interaction network based on Arabidopsis thaliana (A. thaliana) homologs revealed that MAPK, MAPKK, and MAPKKK genes were widely involved in C. oleifera growth and development and in responses to biotic and abiotic stresses. Gene expression analysis revealed that the CoMAPKKK5/CoMAPKKK43/CoMAPKKK49-CoMAPKK4-CoMAPK8 module may play a key role in the cold stress resistance of wild C. oleifera at a high-elevation site in Lu Mountain (LSG). This study can facilitate the mining and utilization of genetic resources of C. oleifera with low-temperature tolerance.
摘要：
背景：低温严重限制了油茶的生长发育（C.油茶）。丝裂原活化蛋白激酶(MAPK)级联反应在冷应激反应中起关键作用。
结果：我们的研究旨在鉴定油茶中的MAPK级联基因，并揭示它们在响应冷胁迫中的作用。在我们的研究中,我们系统地鉴定和分析了油茶的MAPK级联基因家族，包括它们的物理和化学性质，保守的图案，和多个序列比对。此外,我们表征了木瓜中MAPKK激酶（MAPKKK）-MAPK激酶（MAPKK）-MAPK的相互作用网络。通过差异基因表达和实时定量逆转录PCR(qRT-PCR)分析了野生油茶MAPK级联基因抗冷胁迫的分子机制。
结论：在这项研究中，21个MAPK，4个MAPKKs和55个MAPKKs基因在油菜的叶转录组中被鉴定。根据系统发育结果,MAPK分为4组（A，B,C和D),MAPKK分为3组（A，B和D),将MAPKKs分为2组(MEKK和Raf)。基序分析表明，每个亚族的基序都是保守的，同一亚科的大多数基序基本相同。基于拟南芥(A.thaliana)同源物显示MAPK，MAPKK,和MAPKKK基因广泛参与油茶的生长和发育以及对生物和非生物胁迫的响应。基因表达分析表明，CoMAPKKK5/CoMAPKKK43/CoMAPKKKK49-CoMAPKK4-CoMAPK8模块可能在鲁山（LSG）高海拔地区野生油菜籽的抗冷胁迫中起关键作用。本研究可促进耐低温油茶遗传资源的挖掘和利用。
结果：我们的研究旨在鉴定油茶中的MAPK级联基因，并揭示它们在响应冷胁迫中的作用。在我们的研究中,我们系统地鉴定和分析了油茶的MAPK级联基因家族，包括它们的物理和化学性质，保守的图案，和多个序列比对。此外,我们表征了木瓜中MAPKK激酶（MAPKKK）-MAPK激酶（MAPKK）-MAPK的相互作用网络。通过差异基因表达和实时定量逆转录PCR(qRT-PCR)分析了野生油茶MAPK级联基因抗冷胁迫的分子机制。
结论：在这项研究中，21个MAPK，4个MAPKKs和55个MAPKKs基因在油菜的叶转录组中被鉴定。根据系统发育结果,MAPK分为4组（A，B,C和D),MAPKK分为3组（A，B和D),将MAPKKs分为2组(MEKK和Raf)。基序分析表明，每个亚族的基序都是保守的，同一亚科的大多数基序基本相同。基于拟南芥(A.thaliana)同源物显示MAPK，MAPKK,和MAPKKK基因广泛参与油茶的生长和发育以及对生物和非生物胁迫的响应。基因表达分析表明，CoMAPKKK5/CoMAPKKK43/CoMAPKKKK49-CoMAPKK4-CoMAPK8模块可能在鲁山（LSG）高海拔地区野生油菜籽的抗冷胁迫中起关键作用。本研究可促进耐低温油茶遗传资源的挖掘和利用。
