PDF(Pubmed)
Abstract：
The elongation of the mesocotyl plays an important role in the emergence of maize deep-sowing seeds. This study was designed to explore the function of exogenous salicylic acid (SA) and 6-benzylaminopurine (6-BA) in the growth of the maize mesocotyl and to examine its regulatory network. The results showed that the addition of 0.25 mmol/L exogenous SA promoted the elongation of maize mesocotyls under both 3 cm and 15 cm deep-sowing conditions. Conversely, the addition of 10 mg/L exogenous 6-BA inhibited the elongation of maize mesocotyls. Interestingly, the combined treatment of exogenous SA-6-BA also inhibited the elongation of maize mesocotyls. The longitudinal elongation of mesocotyl cells was the main reason affecting the elongation of maize mesocotyls. Transcriptome analysis showed that exogenous SA and 6-BA may interact in the hormone signaling regulatory network of mesocotyl elongation. The differential expression of genes related to auxin (IAA), jasmonic acid (JA), brassinosteroid (BR), cytokinin (CTK) and SA signaling pathways may be related to the regulation of exogenous SA and 6-BA on the growth of mesocotyls. In addition, five candidate genes that may regulate the length of mesocotyls were screened by Weighted Gene Co-Expression Network Analysis (WGCNA). These genes may be involved in the growth of maize mesocotyls through auxin-activated signaling pathways, transmembrane transport, methylation and redox processes. The results enhance our understanding of the plant hormone regulation of mesocotyl growth, which will help to further explore and identify the key genes affecting mesocotyl growth in plant hormone signaling regulatory networks.
摘要：
中胚轴的伸长在玉米深播种子的出现中起着重要作用。本研究旨在探索外源水杨酸（SA）和6-苄基氨基嘌呤（6-BA）在玉米中胚轴生长中的功能，并研究其调控网络。结果表明，在3cm和15cm深播条件下，添加0.25mmol/L外源SA均可促进玉米中胚轴的伸长。相反，添加10mg/L外源6-BA抑制了玉米中胚轴的伸长。有趣的是,外源SA-6-BA的联合处理也抑制了玉米中胚轴的伸长。中胚轴细胞的纵向伸长是影响玉米中胚轴伸长的主要原因。转录组分析表明，外源SA和6-BA可能在中胚轴伸长的激素信号调节网络中相互作用。生长素（IAA）相关基因的差异表达，茉莉酸（JA），油菜素类固醇(BR),细胞分裂素(CTK)和SA信号通路可能与外源SA和6-BA对中胚轴生长的调控有关。此外,通过加权基因共表达网络分析（WGCNA）筛选了可能调节中胚轴长度的五个候选基因。这些基因可能通过生长素激活的信号通路参与玉米中胚轴的生长,跨膜运输，甲基化和氧化还原过程。结果增强了我们对中胚轴生长的植物激素调节的理解，这将有助于进一步探索和识别植物激素信号调节网络中影响中胚轴生长的关键基因。
