A gain-of-function mutation of OsMAPK6 leads to long grain in rice
Lina Xiong,
Lubin Tan,
Ran Xu,
Zuofeng Zhu,
Xianyou Sun,
Hongying Sun,
Chuanqing Sun
Affiliations
Lina Xiong
State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China; National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Lubin Tan
National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Ran Xu
National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Zuofeng Zhu
National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Xianyou Sun
National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
Hongying Sun
National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China; Corresponding authors.
Chuanqing Sun
State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China; National Center for Evaluation of Agricultural Wild Plants (Rice), Beijing Key Laboratory of Crop Genetic Improvement, Laboratory of Crop Heterosis and Utilization, Ministry of Education, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China; Corresponding authors.
Grain size is one of the most important agronomic traits controlling grain yield. Development of novel germplasm with large grains would be beneficial for crop improvement. We report the genetic identification and functional analysis of the LONG GRAIN 6 (LOG6) gene, which is identical to MITOGEN-ACTIVATED PROTEIN KINASE 6 (OsMAPK6), affecting grain length of rice. Map-based cloning revealed that the long-grain phenotype of log6-D results from a glutamine (E) to lysine (K) mutation in the conserved TEY motif of OsMAPK6. In near-isogenic lines (NILs), the log6-D allele increased grain length and grain yield of Guichao 2 (GC2), Teqing (TQ), and 93–11. Sequence analysis revealed 10 OsMAPK6 haplotypes, with xian (indica) and geng (japonica) harboring different haplotypes. Our findings shed light on the function of MAPKs and offer a novel dominant allele for improving the grain yield of rice.
