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1.  Transcriptional and hormonal regulation of petal and stamen development by STAMENLESS, the tomato (Solanum lycopersicum L.) orthologue to the B-class APETALA3 gene 
Journal of Experimental Botany  2014;65(9):2243-2256.
Summary
Characterization of stamenless mutants reveals that petal and stamen identity in tomato depends on gene–hormone interactions, as mediated by the tomato APETALA3 orthologue STAMENLESS gene (SL, syn. TAP3, SlDEF, LeAP3).
Four B-class MADS box genes specify petal and stamen organ identities in tomato. Several homeotic mutants affected in petal and stamen development were described in this model species, although the causal mutations have not been identified for most of them. In this study we characterized a strong stamenless mutant in the tomato Primabel cultivar (sl-Pr), which exhibited homeotic conversion of petals into sepals and stamens into carpels and we compared it with the stamenless mutant in the LA0269 accession (sl-LA0269). Genetic complementation analysis proved that both sl mutants were allelic. Sequencing revealed point mutations in the coding sequence of the Tomato APETALA3 (TAP3) gene of the sl-Pr genome, which lead to a truncated protein, whereas a chromosomal rearrangement in the TAP3 promoter was detected in the sl-LA0269 allele. Moreover, the floral phenotype of TAP3 antisense plants exhibited identical homeotic changes to sl mutants. These results demonstrate that SL is the tomato AP3 orthologue and that the mutant phenotype correlated to the SL silencing level. Expression analyses showed that the sl-Pr mutation does not affect the expression of other tomato B-class genes, although SL may repress the A-class gene MACROCALYX. A partial reversion of the sl phenotype by gibberellins, gene expression analysis, and hormone quantification in sl flowers revealed a role of phytohormones in flower development downstream of the SL gene. Together, our results indicated that petal and stamen identity in tomato depends on gene–hormone interactions, as mediated by the SL gene.
doi:10.1093/jxb/eru089
PMCID: PMC4036497  PMID: 24659487
APETALA3; B-class gene; flower morphogenesis; hormone regulation; Solanum lycopersicum; STAMENLESS; tomato.
2.  Marker-based linkage map of Andean common bean (Phaseolus vulgaris L.) and mapping of QTLs underlying popping ability traits 
BMC Plant Biology  2012;12:136.
Background
Nuña bean is a type of ancient common bean (Phaseolus vulgaris L.) native to the Andean region of South America, whose seeds possess the unusual property of popping. The nutritional features of popped seeds make them a healthy low fat and high protein snack. However, flowering of nuña bean only takes place under short-day photoperiod conditions, which means a difficulty to extend production to areas where such conditions do not prevail. Therefore, breeding programs of adaptation traits will facilitate the diversification of the bean crops and the development of new varieties with enhanced healthy properties. Although the popping trait has been profusely studied in maize (popcorn), little is known about the biology and genetic basis of the popping ability in common bean. To obtain insights into the genetics of popping ability related traits of nuña bean, a comprehensive quantitative trait loci (QTL) analysis was performed to detect single-locus and epistatic QTLs responsible for the phenotypic variance observed in these traits.
Results
A mapping population of 185 recombinant inbred lines (RILs) derived from a cross between two Andean common bean genotypes was evaluated for three popping related traits, popping dimension index (PDI), expansion coefficient (EC), and percentage of unpopped seeds (PUS), in five different environmental conditions. The genetic map constructed included 193 loci across 12 linkage groups (LGs), covering a genetic distance of 822.1 cM, with an average of 4.3 cM per marker. Individual and multi-environment QTL analyses detected a total of nineteen single-locus QTLs, highlighting among them the co-localized QTLs for the three popping ability traits placed on LGs 3, 5, 6, and 7, which together explained 24.9, 14.5, and 25.3% of the phenotypic variance for PDI, EC, and PUS, respectively. Interestingly, epistatic interactions among QTLs have been detected, which could have a key role in the genetic control of popping.
Conclusions
The QTLs here reported constitute useful tools for marker assisted selection breeding programs aimed at improving nuña bean cultivars, as well as for extending our knowledge of the genetic determinants and genotype x environment interaction involved in the popping ability traits of this bean crop.
doi:10.1186/1471-2229-12-136
PMCID: PMC3490973  PMID: 22873566

Results 1-2 (2)