The Key Laboratory of Oasis Eco-Agriculture, College of Agriculture, Shihezi University, Shihezi, Xinjiang, China.
Special Plant Genomics Laboratory, College of Life Sciences, Shihezi University, Shihezi, Xinjiang, China.
PLoS One. 2019 Apr 19;14(4):e0215771. doi: 10.1371/journal.pone.0215771. eCollection 2019.
Plant phosphatidylethanolamine-binding protein (PEBP) is comprised of three clades: FLOWERING LOCUS T (FT), TERMINAL FLOWER1 (TFL1) and MOTHER OF FT AND TFL1 (MFT). FT/TFL1-like clades regulate identities of the determinate and indeterminate meristems, and ultimately affect flowering time and plant architecture. MFT is generally considered to be the ancestor of FT/TFL1, but its function is not well understood. Here, two MFT homoeologous gene pairs in Gossypium hirsutum, GhMFT1-A/D and GhMFT2-A/D, were identified by genome-wide identification of MFT-like genes. Detailed expression analysis revealed that GhMFT1 and GhMFT2 homoeologous genes were predominately expressed in ovules, and their expression increased remarkably during ovule development but decreased quickly during seed germination. Expressions of GhMFT1 and GhMFT2 homoeologous genes in germinating seeds were upregulated in response to abscisic acid (ABA), and their expressions also responded to gibberellin (GA). In addition, ectopic overexpression of GhMFT1 and GhMFT2 in Arabidopsis inhibited seed germination at the early stage. Gene transcription analysis showed that ABA metabolism genes ABA-INSENSITIVE3 (ABI3) and ABI5, GA signal transduction pathway genes REPRESSOR OF ga1-3 (RGA) and RGA-LIKE2 (RGL2) were all upregulated in the 35S:GhMFT1 and 35S:GhMFT2 transgenic Arabidopsis seeds. GhMFT1 and GhMFT2 localize in the cytoplasm and nucleus, and both interact with a cotton bZIP transcription factor GhFD, suggesting that both of GhMFT1, 2 have similar intracellular regulation mechanisms. Taken together, the results suggest that GhMFT1 and GhMFT2 may act redundantly and differentially in the regulation of seed germination.
植物磷酯乙醇胺结合蛋白（PEBP）由三个分支组成：开花位点 T（FT）、终端花 1（TFL1）和 FT 和 TFL1 的母亲（MFT）。FT/TFL1 样分支调节决定和不定芽的身份，最终影响开花时间和植物结构。MFT 通常被认为是 FT/TFL1 的祖先，但它的功能尚未得到很好的理解。在这里，通过对 MFT 样基因的全基因组鉴定，在 Gossypium hirsutum 中鉴定了两个 MFT 同源基因对 GhMFT1-A/D 和 GhMFT2-A/D。详细的表达分析表明，GhMFT1 和 GhMFT2 同源基因主要在胚珠中表达，其表达在胚珠发育过程中显著增加，但在种子萌发过程中迅速下降。萌发种子中 GhMFT1 和 GhMFT2 同源基因的表达对脱落酸（ABA）上调，其表达也对赤霉素（GA）有反应。此外，在拟南芥中异位过表达 GhMFT1 和 GhMFT2 会抑制种子在早期萌发。基因转录分析表明，ABA 代谢基因 ABA 不敏感 3（ABI3）和 ABI5、GA 信号转导途径基因 REPRESSOR OF ga1-3（RGA）和 RGA-LIKE2（RGL2）在 35S:GhMFT1 和 35S:GhMFT2 转基因拟南芥种子中均上调。GhMFT1 和 GhMFT2 定位于细胞质和细胞核中，并且都与棉花 bZIP 转录因子 GhFD 相互作用，这表明 GhMFT1、2 具有相似的细胞内调节机制。综上所述，这些结果表明 GhMFT1 和 GhMFT2 可能在调控种子萌发中具有冗余和差异的作用。
