biologia plantarum

Biologia plantarum 61:85-94, 2017 | DOI: 10.1007/s10535-016-0632-4

Characterization of a rice dwarf and narrow leaf 2 mutant

Y. M. N. Adedze¹, X. J. Wei¹, Z. H. Sheng¹, G. A. Jiao¹, S. Q. Tang^1,*, P. S. Hu^1,*

¹ State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China

The rice dwarf and narrow leaf mutant 2 (dnl2) is dwarfed and forms narrow and brittle leaves. Its dwarfness was shown to be due to its shortened internodes resulting from a reduced size of the internode parenchyma cells. Its narrow and brittle leaves were attributed to a compromised ability to form vascular bundles but a reduced fiber content and thin cortical layer. However, response to the application of either gibberellin or brassinolide was not different between dnl2 and its wild type. Transcription profiling indicates that a number of cell division/expansion-associated and crude fiber synthesis-related genes were down-regulated in the mutant. A genetic analysis revealed that the mutant phenotype was under monogenic control, and the gene responsible was mapped to a 50.1 kb genomic region on the long arm of chromosome 10. This region was shown to harbor 10 open reading frames. Although transcription profiling these genes indicates that three were differentially transcribed in the mutant, there was no sequence polymorphism in the coding sequence between the mutant and the wild type alleles.

Keywords: fine-mapping; leaf and stem structure; mechanical strength; Oryza sativa; transcriptional analysis

Subjects: mutants; gene mapping; mechanical strength; growth analysis; vascular bundles; gene expression; rice

Received: October 29, 2015; Revised: December 27, 2015; Accepted: January 13, 2016; Published: January 1, 2017Show citation