AUTHOR=Lv Guangde , Jin Xuemei , Wang Hui , Wang Yijun , Wu Qun , Wu Haimeng , Jiang Fangshan , Ma Yanming , An Yanrong , Zhang Mingxia , Guo Ying , Li Sishen 

TITLE=Cloning a novel reduced-height (Rht) gene TaOSCA1.4 from a QTL in wheat

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1381243

DOI=10.3389/fpls.2024.1381243

ISSN=1664-462X

ABSTRACT=<p>Reducing plant height (PH) is one of the core contents of the “Green Revolution”, which began in the 1960s in wheat. A number of 27 reduced-height (<italic>Rht</italic>) genes have been identified and a great number of quantitative trait loci (QTLs) for PH have been mapped on all 21 chromosomes. Nonetheless, only several genes regulated PH have been cloned. In this study, we found the interval of QTL <italic>QPh-1B</italic> included an EST-SSR marker <italic>swes1079</italic>. According to the sequence of <italic>swes1079</italic>, we cloned the <italic>TaOSCA1.4</italic> gene. We developed a CAPS marker to analyze the variation across a natural population. The result showed that the PH was significantly different between the two haplotypes of <italic>TaOSCA1.4–1B</italic> under most of the 12 environments and the average values of irrigation and rainfed conditions. This result further demonstrated that <italic>TaOSCA1.4</italic> was associated with PH. Then, we validated the <italic>TaOSCA1.4</italic> via RNAi technology. The average PHs of the wild-type (WT), RNAi lines 1 (Ri-1) and 2 (Ri-2) were 94.6, 83.6 and 79.2 cm, respectively, with significant differences between the WT and Ri-1 and Ri-2. This result indicated that the <italic>TaOSCA1.4</italic> gene controls PH. <italic>TaOSCA1.4</italic> is a constitutively expressed gene and its protein localizes to the cell membrane. <italic>TaOSCA1.4</italic> gene is a member of the <italic>OSCA</italic> gene family, which regulates intracellular Ca<sup>2+</sup> concentration. We hypothesized that knock down mutants of <italic>TaOSCA1.4</italic> gene reduced regulatory ability of Ca<sup>2+</sup>, thus reducing the PH. Furthermore, the cell lengths of the knock down mutants are not significantly different than that of WT. We speculate that <italic>TaOSCA1.4</italic> gene is not directly associated with gibberellin (GA), which should be a novel mechanism for a wheat <italic>Rht</italic> gene.</p>