TY  - EJOU
AU  - He, Ling 
AU  - Tao, Shun 
AU  - Wang, Qian 
AU  - Yin, Yu-Pei 
AU  - He, Xin-Yu 
AU  - Shi, Shuo 
AU  - Wang, Chun-Yan 

TI  - Expression Analysis and Functional Validation of Lily <i>LoWRKY22</i>
T2  - Phyton-International Journal of Experimental Botany

PY  - 2026
VL  - 95
IS  - 6
SN  - 1851-5657

AB  - As essential regulatory proteins, WRKY transcription factors participate in the regulation of plant growth, development and stress resistance; however, the functions of <i>LoWRKY22</i> in the ‘Siberia’ cultivar of <i>Lilium</i> remain uncharacterized. In this study, <i>LoWRKY22</i> was cloned and subjected to comprehensive functional analyses. Phylogenetic analysis revealed that <i>LoWRKY22</i> belongs to the WRKY-IIe type subgroup, featuring a conserved WRKY domain and a C2H2-type zinc finger motif, indicating evolutionary conservation with WRKY homologs from <i>Arabidopsis thaliana</i>. Subcellular localization and transactivation assays confirmed its nuclear localization and transcriptional activation activity, supporting its role as a transcriptional regulator. Structural characterization of the <i>LoWRKY22</i> promoter identified multiple <i>cis</i>-elements responsive to light, low temperature, and gibberellin, suggesting its involvement in environmental and hormonal signaling pathways. Tissue expression analysis demonstrated predominant expression of <i>LoWRKY22</i> in leaves, consistent with its proposed roles in photosynthesis- and senescence-related processes. The heterologous overexpression of <i>LoWRKY22</i> in <i>Arabidopsis thaliana</i> induced early flowering, reduced plant height, and accelerated silique maturation relative to those in wild-type plants. Quantitative real-time polymerase chain reaction (PCR) revealed that <i>LoWRKY22</i> overexpression significantly upregulated senescence-associated genes (<i>AtWRKY53</i>, <i>AtSAG12</i>, and <i>AtSAG13</i>) and flowering-promoting genes (<i>AtFT</i> and <i>AtAP1</i>), while downregulating the floral repressor <i>AtFLC</i>. These findings indicate that <i>LoWRKY22</i> functions as a positive regulator of flowering and senescence, potentially coordinating the transition from vegetative to reproductive growth via the modulation of key regulatory networks. Collectively, this research firstly identified and explored the functions of <i>LoWRKY22</i> in the‘Siberia’ cultivar of <i>Lilium</i>, elucidating its regulatory role in growth-phase transitions and establishing a molecular foundation for its potential utilization as a candidate gene in genetic breeding programs aimed at optimizing growth, flowering time, and developmental traits in lilies.
KW  - <i>Lilium</i> ‘Siberia’; <i>LoWRKY22</i>; WRKY transcription factor; flowering; senescence; <i>Arabidopsis</i>; heterologous transformation; phylogenetic analysis

DO  - 10.32604/phyton.2026.081349