Genome-wide identification and characterization of CONSTANS-like gene family in radish (Raphanus sativus).

Floral induction that initiates bolting and flowering is crucial for reproductive fitness in radishes. CONSTANS-like (CO-like, COL) genes play an important role in the circadian clock, which ensures regular development through complicated time-keeping mechanisms. However, the specific biological and functional roles of each COL transcription factor gene in the radish remain unknown. In this study, we performed a genome-wide identification of COL genes in the radish genome of three cultivars including 'Aokubi', 'kazusa' and 'WK10039', and we analyzed their exon-intron structure, gene phylogeny and synteny, and expression levels in different tissues. The bioinformatics analysis identified 20 COL transcription factors in the radish genome, which were divided into three subgroups (Group I to Group III). RsaCOL-09 and RsaCOL-12 might be tandem duplicated genes, whereas the others may have resulted from segmental duplication. The Ka/Ks ratio indicated that all the COL genes in radish, Arabidopsis, Brassica rapa, Brassica oleracea, Capsella rubella and rice were under purifying selection. We identified 6 orthologous and 19 co-orthologous COL gene pairs between the radish and Arabidopsis, and we constructed an interaction network among these gene pairs. The expression values for each COL gene during vegetable and flower development showed that the majority of Group I members had similar expression patterns. In general, the expression of radish COL genes in Groups I and III decreased during development, whereas the expression of radish COL genes in Group II first increased and then decreased. Substantial numbers of radish COL genes were differentially expressed after vernalization treatment. The expression levels of RsaCOL-02 and RsaCOL-04 were significantly increased during vernalization treatment, while the expression of RsaCOL-10 was significantly decreased. These outcomes provide insights for improving the genetic control of bolting and flowering in radish and other root vegetable crops, and they facilitate genetic improvements to radish yields and quality

Genome-wide identification and characterization of Dof transcription factors in eggplant (Solanum melongena L.)

Eggplant (Solanum melongena L.) is an important vegetable cultivated in Asia, Africa and southern Europe and, following tomato and pepper, ranks as the third most important solanaceous vegetable crop. The Dof (DNA-binding with one finger) family is a group of plant-specific transcription factors that play important roles in plant growth, development, and response to biotic and abiotic stresses. The genes in the Dof family have been identified and analysed in many plant species, but the information remains lacking for eggplant. In the present study, we identified 29 SmeDof members from the eggplant genome database, which were classifed into nine subgroups. The phylogeny, gene structure, conserved motifs and homologous genes of SmeDof genes were comprehensively investigated. Subsequently, we analysed the expression patterns of SmeDof genes in six different eggplant subspecies. The results provide novel insights into the family of SmeDof genes and will promote the understanding of the structure and function of Dof genes in eggplant, and the role of Dof expression during stress

Long chain 1,14-diols as potential indicators for upper water stratification in the open South China Sea

Long chain 1,14-diols have been widely studied in typical upwelling areas, but less investigated in open seas. In this study the 1,14-diols in a sediment core, covering a history between 42 ka and 12 ka, were studied to investigate their potential to indicate upper water stratification in the open northern South China Sea (SCS). Downcore records of 1,14-diol fractional abundances, diol index 1 (DI-1) and diol index 2 (DI-2) changed in parallel, with a prominent increase at -14.5 ka, likely corresponding with the Bolling warming event. This pattern is different from what has been observed in typical upwelling regimes, showing an insignificant relationship between DI-1 and DI-2. Moreover, these records showed a generally inverse variation pattern with records of primary productivity, further suggesting that they are not likely applicable as upwelling indicators in the study area. However, the 1,14-diol records changed positively with sea surface temperature (SST), as well as the difference between SST and subsurface-temperature, hence suggesting their potential to indicate upper water column stratification in the open SCS. This occurrence might be associated with the productivity of 1,14-diol precursor (i.e., Proboscia diatom), which is sensitive to the variation of mixed layer depth in oligotrophic open oceans and lacks of competitiveness relative to the more heavily silicified diatoms under normal Si replete upwelling conditions. Our result also suggested that the East Asian monsoon may have played an important role to modulate riverine terrigenous organic matter input to the study area