Key Laboratory of Biological Resource Protection and Utilization of Tarim Basin, Xinjiang Production and Construction Group, 843300, Alar, China.
College of Life Science and Technology, Tarim University, 843300, Alar, China.
BMC Genomics. 2024 Mar 28;25(1):317. doi: 10.1186/s12864-024-10221-5.
The growth-regulating factor-interacting factor (GIF) gene family plays a vital role in regulating plant growth and development, particularly in controlling leaf, seed, and root meristem homeostasis. However, the regulatory mechanism of heteromorphic leaves by GIF genes in Populus euphratica as an important adaptative trait of heteromorphic leaves in response to desert environment remains unknown.
This study aimed to identify and characterize the GIF genes in P. euphratica and other five Salicaceae species to investigate their role in regulating heteromorphic leaf development. A total of 27 GIF genes were identified and characterized across six Salicaceae species (P. euphratica, Populus pruinose, Populus deltoides, Populus trichocarpa, Salix sinopurpurea, and Salix suchowensis) at the genome-wide level. Comparative genomic analysis among these species suggested that the expansion of GIFs may be derived from the specific Salicaceae whole-genome duplication event after their divergence from Arabidopsis thaliana. Furthermore, the expression data of PeGIFs in heteromorphic leaves, combined with functional information on GIF genes in Arabidopsis, indicated the role of PeGIFs in regulating the leaf development of P. euphratica, especially PeGIFs containing several cis-acting elements associated with plant growth and development. By heterologous expression of the PeGIF3 gene in wild-type plants (Col-0) and atgif1 mutant of A. thaliana, a significant difference in leaf expansion along the medial-lateral axis, and an increased number of leaf cells, were observed between the overexpressed plants and the wild type.
PeGIF3 enhances leaf cell proliferation, thereby resulting in the expansion of the central-lateral region of the leaf. The findings not only provide global insights into the evolutionary features of Salicaceae GIFs but also reveal the regulatory mechanism of PeGIF3 in heteromorphic leaves of P. euphratica.
生长调节因子相互作用因子（GIF）基因家族在调节植物生长发育中起着至关重要的作用，特别是在控制叶、种子和根分生组织的稳态中。然而，GIF 基因在胡杨作为一种应对沙漠环境的异形叶重要适应特性中调控异形叶的机制尚不清楚。
本研究旨在鉴定和表征胡杨和其他五种杨柳科物种中的 GIF 基因，以研究它们在调控异形叶发育中的作用。在六个杨柳科物种（胡杨、白杨、山杨、毛白杨、紫柳和垂柳）的全基因组水平上共鉴定和表征了 27 个 GIF 基因。这些物种之间的比较基因组分析表明，GIF 的扩张可能源自它们与拟南芥分化后的杨柳科特异性全基因组复制事件。此外，异形叶中 PeGIFs 的表达数据，结合拟南芥中 GIF 基因的功能信息，表明 PeGIFs 在调节胡杨叶片发育中的作用，特别是含有与植物生长发育相关的几个顺式作用元件的 PeGIFs。通过在野生型植物（Col-0）和拟南芥 atgif1 突变体中异源表达 PeGIF3 基因，观察到叶片在中侧轴上的扩展以及叶片细胞数量的增加在过表达植株和野生型之间存在显著差异。
PeGIF3 增强了叶片细胞的增殖，从而导致叶片中侧区域的扩展。这些发现不仅为杨柳科 GIFs 的进化特征提供了全面的见解，还揭示了 PeGIF3 在胡杨异形叶中的调控机制。
