A large presence/absence variation in the promotor of the ClLOG gene determines trichome elongation in watermelon

Yuyuan Ma, Yu Wang, Zhiqin Zhou, Runqin Zhang, Yiru Xie, Yihan Zhang, Yongming Bo, Xiaolong Lyu, Jinghua Yang, Mingfang Zhang & Zhongyuan Hu

Theoretical and Applied Genetics; 9 April 2024; vol.137; article 98

Key message

The ClLOG gene encoding a cytokinin riboside 5ʹ-monophosphate phosphoribohydrolase determines trichome length in watermelon, which is associated with its promoter variations.

Abstract

Trichomes, which are differentiated from epidermal cells, are special accessory structures that cover the above-ground organs of plants and possibly contribute to biotic and abiotic stress resistance. Here, a bulked segregant analysis (BSA) of an F₂ population with significant variations in trichome length was undertaken. A 1.84-Mb candidate region on chromosome 10 was associated with trichome length. Resequencing and fine-mapping analyses indicated that a 12-kb structural variation in the promoter of Cla97C10G203450 (ClLOG) led to a significant expression difference in this gene in watermelon lines with different trichome lengths. In addition, a virus-induced gene silencing analysis confirmed that ClLOG positively regulated trichome elongation. These findings provide new information and identify a potential target gene for controlling multicellular trichome elongation in watermelon.

See https://link.springer.com/article/10.1007/s00122-024-04601-4