摘要
The wheat grain number per spike （GNPS） is a major yield-limiting factor in wheat-breeding programs. Germplasms with a high GNPS are therefore valuable for increasing wheat yield potential. To investigate the molecular characteristics of young spike development in large-spike wheat germplasms with high GNPS, we performed gene and protein expression profiling analysis with three high-GNPS wheat lines （Pubing 3228, Pubing 3504 and 4844-12） and one Iow-GNPS control variety （Fukuho）. The phenotypic data for the spikes in two growth seasons showed that the GNPS of the three large-spike wheat lines were significantly higher than that of the Fukuho control line. The Affymetrix wheat chip and isobaric tags for relative and absolute quantitation-tandam mass spectrometry （iTRAQ-MS/MS） technology were employed for gene and protein expression profiling analyses of young spike development, respectively, at the floret primordia differentiation stage. A total of 598 differentially expressed transcripts （270 up-regulated and 328 down-regulated） and 280 proteins （122 up- regulated and 158 down-regulated） were identified in the three high-GNPS lines compared with the control line. We found that the expression of some floral development-related genes, including Wknoxlb, the AP2 domain protein kinase and the transcription factor HUA2, were up-regulated in the high-GNPS lines. The expression of the SHEPHERD （SHD） gene was up-regulated at both the transcript and protein levels. Overall, these results suggest that multiple regulatory pathways, including the CLAVATA pathway and the meristem-maintaining KNOX protein pathway, take part in the development of the high-GNPS phenotype in our wheat germplasms.
The wheat grain number per spike （GNPS） is a major yield-limiting factor in wheat-breeding programs. Germplasms with a high GNPS are therefore valuable for increasing wheat yield potential. To investigate the molecular characteristics of young spike development in large-spike wheat germplasms with high GNPS, we performed gene and protein expression profiling analysis with three high-GNPS wheat lines （Pubing 3228, Pubing 3504 and 4844-12） and one Iow-GNPS control variety （Fukuho）. The phenotypic data for the spikes in two growth seasons showed that the GNPS of the three large-spike wheat lines were significantly higher than that of the Fukuho control line. The Affymetrix wheat chip and isobaric tags for relative and absolute quantitation-tandam mass spectrometry （iTRAQ-MS/MS） technology were employed for gene and protein expression profiling analyses of young spike development, respectively, at the floret primordia differentiation stage. A total of 598 differentially expressed transcripts （270 up-regulated and 328 down-regulated） and 280 proteins （122 up- regulated and 158 down-regulated） were identified in the three high-GNPS lines compared with the control line. We found that the expression of some floral development-related genes, including Wknoxlb, the AP2 domain protein kinase and the transcription factor HUA2, were up-regulated in the high-GNPS lines. The expression of the SHEPHERD （SHD） gene was up-regulated at both the transcript and protein levels. Overall, these results suggest that multiple regulatory pathways, including the CLAVATA pathway and the meristem-maintaining KNOX protein pathway, take part in the development of the high-GNPS phenotype in our wheat germplasms.
基金
supported by grants from the National Basic Research Program of China(973 Program,2011CB100104)
the National High-Tech R&D Program of China(2011AA100101)
the National Natural Science Foundation of China(31071416)
the National Key Technologies R&D Program of China during the 12th FiveYear Plan period(2013BAD01B02)
