Authors: Xiaolei Feng Pengke Zhao Jianqin Hao Jinquan Hu Dingming Kang Huaqi Wang
Publish Date: 2011/03/26
Volume: 106, Issue: 3, Pages: 455-463
Abstract
Sorbitol promotes plantlet regeneration frequency PRF of rice calli To better understand this phenomenon calli of upland rice cv HD65 were induced on medium containing 10 g sorbitol/L and subcultured and regenerated on media containing 20 and 40 g sorbitol/L respectively Using complementary DNA cDNAamplified fragment length polymorphism AFLP analysis we investigated differential gene expression between sorbitolsupplemented SC and sorbitolfree calli NC during the regeneration stage From 4000 transcriptderived fragments TDFs we identified 118 differentially expressed TDFs between SC and NC Of these 37 were cloned and sequenced and 12 were further confirmed by semiquantitative reversetranscription polymerase chain reaction RTPCR analysis Database searches indicated that 10 TDFs showed no significant homology to genes with known or putative functions although they were previously reported to be expressed in rice calli These cDNAs might encode novel proteins related to plantlet regeneration Of all the 27 wellknown TDFs 351 were highly expressed in SC and had roles in signal transduction 135 transcription and translation 135 and regulation 81 Four TDFs were related to plant growth and regeneration TDF5 TDF17 TDF21 and TDF26 which showed homologies to a nucleoside diphosphate kinase NDPK a cyclin a receptorlike protein kinase precursor and TCP1 respectively Furthermore 351 were related to metabolism 270 to energy and 81 to defense These results suggest that in addition to its roles as a carbon source and an osmotic regulator sorbitol may also act as a chemical signal to directly or indirectly alter gene expression Sorbitol exerts its effects via complex transcriptional networks to enhance PRF of calli
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