Deficiency of a peroxisomal NADP-isocitrate dehydrogenase leads to dwarf plant and defect seed in upland cotton.

The NADP-isocitrate dehydrogenase-encoded gene with a C-terminus tripeptide Proline-Lysine-Leucine was localized in the peroxisome. It was highly expressed in stems and ovules of 15 days post-anthesis and responded to multiple external stimuli in upland cotton. An upland cotton mutant () was identified by flanking sequence amplification and genome variation detection that exogenous sequence was inserted in the middle of the 12th intron of , resulting in the deficiency of gene expression. The mutant displayed a dwarf plant phenotype when grown under field or greenhouse conditions, and functioned as an incomplete dominance on plant height. The germination rate of mutant seed from greenhouse-grown plants was dramatically lower than that from field-grown plants, which indicated that GhperICDH plays a critical role in seed maturation and germination. Therefore, is indispensable in the development of stems and seeds and functions in the adaptability of cotton to the environment. The mutant provides insight into the function of peroxisomal ICDH and may contribute to the genetic improvement in cotton.