In plants and microbes, sucrose phosphate synthase (SPS) is an important enzyme in sucrose biosynthesis. Several different isozymes of SPS exist in plants. Genomic and EST sequence data from Arabidopsis, rice and maize has been analyzed. This analysis has revealed that the Arabidopsis genome contains four unique SPS genes. The rice databases (Monsanto proprietary, and public databases) contain five unique full-length SPS genes. Using the Monsanto maize EST and genomic sequence databases, we have identified five full length and two partial SPS sequences, bringing the total number of presently known maize SPS genes to at least seven. Phylogenetic analysis of all known SPS sequences revealed several putative evolutionary branches of SPS. We have classified SPS genes into three major groups in higher plants, all with distinct features from the known microbial SPS genes. Furthermore, this analysis suggests evolutionary divergence of monocotyledonous (monocot) and dicotyledonous (dicot) SPS sequences. The evidence suggests that several gene duplication events occurred at various points during evolution, both before and after the monocot/dicot split. It appears that at least one of the major forms of SPS genes may have evolved after the divergence of monocots and dicots. In addition, several more recent gene duplication events may have occurred after maize/rice speciation, giving rise to additional SPS genes in maize. Some of the variants lack one or more of the presently known regulatory sites, implying that this evolutionary divergence may have given rise to enzymes with functional differences. We present evidence from transcript distribution studies using cDNA libraries as well as transcriptional profiling experiments and propose that specific SPS genes have diverse patterns of expression that are sometimes responsive to environmental signals. Our data suggests that higher plant SPS isozymes differ with respect to their patterns of expression and regulation and that our proposed phylogenetic classification reflects specific functional categories for higher plant SPS isozymes.
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http://dx.doi.org/10.1016/j.jplph.2006.04.014 | DOI Listing |
Int J Biol Macromol
January 2025
College of Horticulture, Institute of Genetics and Breeding in Horticultural Plants, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China. Electronic address:
Sucrose is an important factor affecting plant growth and fruit quality, but the molecular regulatory mechanism of sucrose biosynthesis in longan is not yet understood. Here, we characterized a transcription factor, DlbHLH68, positively regulates sucrose accumulation in longan. Subcellular localization and transcriptional activity analysis indicated that DlbHLH68 is a nuclear transcriptional activator.
View Article and Find Full Text PDFThromb Res
December 2024
Department of Obstetrics and Gynaecology, Trinity College Dublin, Dublin, Ireland; Trinity St. James's Cancer Institute, Dublin, Ireland. Electronic address:
Background: Tumour type, treatment and patient related factors contribute to cancer associated venous thromboembolism (VTE), however, the role of each factor and the mechanisms involved are not understood.
Aim: To assess the role of the tumour, and of chemotherapy, in mediating the procoagulant response associated with VTE in gynaecological cancer patients.
Methods: Gynaecological cancer patients who developed VTE during follow-up (n = 59) (VTE+) were matched with treatment naïve(treatment (-)(VTE-)(n = 120) and chemotherapy treated patients(treatment (+)(VTE-) (n = 57)).
Front Plant Sci
December 2024
Hubei Key Laboratory of Biological Resources Protection and Utilization, Hubei Minzu University, Enshi, China.
Selenium nanoparticles (SeNPs) can be absorbed by plants, thereby affecting plant physiological activity, regulating gene expression, and altering metabolite content. However, the molecular mechanisms by which exogenous selenium affects coll.et Hemsl plant secondary metabolites remain unclear.
View Article and Find Full Text PDFBMC Plant Biol
December 2024
College of Agronomy, Anhui Agricultural University, Key Laboratory of Wheat Biology and Genetic Improvement On Southern Yellow & Huai River Valley, Ministry of Agriculture, Hefei, 230036, Anhui, China.
Plant Physiol
December 2024
Université Paris-Saclay, INRAE, AgroParisTech, Institute Jean-Pierre Bourgin for Plant Sciences (IJPB), 78000 Versailles, France.
Autophagy is a vesicular mechanism that plays a fundamental role in nitrogen remobilization from senescing leaves to seeds. The Arabidopsis (Arabidopsis thaliana) autophagy (atg) mutants exhibit early senescence, reduced biomass, and low seed yield. The atg seeds also exhibit major changes in N and C concentrations.
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