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61.
Simona Nardozza Helen L. Boldingh M. Peggy Kashuba Regina Feil Dan Jones Amali H. Thrimawithana Hilary S. Ireland Marine Philippe Mark W. Wohlers Tony K. McGhie Mirco Montefiori John E. Lunn Andrew C. Allan Annette C. Richardson 《Plant, cell & environment》2020,43(4):819-835
Kiwifruit (Actinidia spp.) is a recently domesticated fruit crop with several novel-coloured cultivars being developed. Achieving uniform fruit flesh pigmentation in red genotypes is challenging. To investigate the cause of colour variation between fruits, we focused on a red-fleshed Actinidia chinensis var. chinensis genotype. It was hypothesized that carbohydrate supply could be responsible for this variation. Early in fruit development, we imposed high or low (carbon starvation) carbohydrate supplies treatments; carbohydrate import or redistribution was controlled by applying a girdle at the shoot base. Carbon starvation affected fruit development as well as anthocyanin and carbohydrate metabolite concentrations, including the signalling molecule trehalose 6-phosphate. RNA-Seq analysis showed down-regulation of both gene-encoding enzymes in the anthocyanin and carbohydrate biosynthetic pathways. The catalytic trehalose 6-phosphate synthase gene TPS1.1a was down-regulated, whereas putative regulatory TPS7 and TPS11 were strongly up-regulated. Unexpectedly, under carbon starvation MYB10, the anthocyanin pathway regulatory activator was slightly up-regulated, whereas MYB27 was also up-regulated and acts as a repressor. To link these two metabolic pathways, we propose a model where trehalose 6-phosphate and the active repressor MYB27 are involved in sensing the carbon starvation status. This signals the plant to save resources and reduce the production of anthocyanin in fruits. 相似文献
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Aureo Banhos Bruno L. Fontes Débora Regina Yogui Mario Henrique Alves Natália Carneiro Ardente Renata Valls Lucas Mendes Barreto Lucas Damásio Átilla Colombo Ferreguetti Andréa Siqueira Carvalho Vitor Roberto Schettino Alexandre Rosa dos Santos Helena Godoy Bergallo Ana Carolina Srbek-Araujo Emilia Patrícia Medici Ariel Canena Arnaud L.J. Desbiez 《Biotropica》2020,52(3):421-426
We report 24 records of giant armadillo roadkill on Brazilian highways in the Cerrado, Pantanal and Amazon biomes illustrating that highways are a threat to this species. However, we also documented the species using underpasses, demonstrating that these structures could help to reduce the risk of roadkill for giant armadillos. 相似文献
64.
Ana Paula Zanatta Leila Zanatta Renata Gonçalves Ariane Zamoner Fátima Regina Mena Barreto Silva 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
The secretory activity of Sertoli cells (SC) is dependent on ion channel functions and protein synthesis and is critical to ongoing spermatogenesis. The aim of this study was to investigate the mechanism of action associated with a non-metabolizable amino acid [14C]-MeAIB (α-(methyl-amino)isobutyric acid) accumulation stimulated by T4 and the role of the integrin receptor in this event, and also to clarify whether the T4 effect on MeAIB accumulation and on Ca2+ influx culminates in cell secretion.Methods
We have studied the rapid and plasma membrane initiated effects of T4 by using 45Ca2+ uptake and [45C]-MeAIB accumulation assays, respectively. Thymidine incorporation into DNA was used to monitor nuclear activity and quinacrine to analyze the secretory activity on SC.Results
The stimulation of MeAIB accumulation by T4 appears to be mediated by the integrin receptor in the plasma membrane since tetrac and RGD peptide were able to nullify the effect of this hormone. In addition, T4 increases extracellular Ca2+ uptake and Ca2+ from intracellular stocks to enhance nuclear activity, but this genomic action seems not to influence SC secretion mediated by T4. Also, the cytoskeleton and ClC-3 chloride channel contribute to the membrane-associated responses of SC.Conclusions
T4 integrin receptor activation ultimately determines the plasma membrane responses on amino acid transport in SC, but it is not involved in calcium influx, cell secretion or the nuclear effect of the hormone.General significance
The integrin receptor activation by T4 may take a role in plasma membrane processes involved in the male reproductive system. 相似文献65.
66.
Mandy L. Wilson Yizhi Cai Regina Hanlon Samantha Taylor Bastien Chevreux Jo?o C. Setubal Brett M. Tyler Jean Peccoud 《Nucleic acids research》2013,41(1):e25
Gene synthesis attempts to assemble user-defined DNA sequences with base-level precision. Verifying the sequences of construction intermediates and the final product of a gene synthesis project is a critical part of the workflow, yet one that has received the least attention. Sequence validation is equally important for other kinds of curated clone collections. Ensuring that the physical sequence of a clone matches its published sequence is a common quality control step performed at least once over the course of a research project. GenoREAD is a web-based application that breaks the sequence verification process into two steps: the assembly of sequencing reads and the alignment of the resulting contig with a reference sequence. GenoREAD can determine if a clone matches its reference sequence. Its sophisticated reporting features help identify and troubleshoot problems that arise during the sequence verification process. GenoREAD has been experimentally validated on thousands of gene-sized constructs from an ORFeome project, and on longer sequences including whole plasmids and synthetic chromosomes. Comparing GenoREAD results with those from manual analysis of the sequencing data demonstrates that GenoREAD tends to be conservative in its diagnostic. GenoREAD is available at www.genoread.org. 相似文献
67.
Kelli Cristina Micocci Ana Carolina Baptista Moreno Martin Cyntia de Freitas Montenegro Araceli Cristina Durante Normand Pouliot Márcia Regina Cominetti Heloisa Sobreiro Selistre-de-Araujo 《Biochimie》2013
ADAM9 (A Disintegrin And Metalloproteinase 9) is a member of the ADAM protein family which contains a disintegrin domain. This protein family plays key roles in many physiological processes, including fertilization, migration, and cell survival. The ADAM proteins have also been implicated in various diseases, including cancer. Specifically, ADAM9 has been suggested to be involved in metastasis. To address this question, we generated ADAM9 knockdown clones of MDA-MB-231 breast tumor cells using silencing RNAs that were tested for cell adhesion, proliferation, migration and invasion assays. In RNAi-mediated ADAM9 silenced MDA-MB-231 cells, the expression of ADAM9 was lower from the third to the sixth day after silencing and inhibited tumor cell invasion in matrigel by approximately 72% when compared to control cells, without affecting cell adhesion, proliferation or migration. In conclusion, the generation of MDA-MB-231 knockdown clones lacking ADAM9 expression inhibited tumor cell invasion in vitro, suggesting that ADAM9 is an important molecule in the processes of invasion and metastasis. 相似文献
68.
T. C. Brachert M. Reuter S. Krüger A. Böcker H. Lohmann R. Mertz-Kraus C. Fassoulas 《Coral reefs (Online)》2013,32(4):1013-1023
The predicted sea surface temperature (SST) rise over the next decades is likely hazardous to coral health because precipitation of the calcareous skeleton depends primarily on SST. Temperature modulates vertical growth and density of the skeleton with seasonal SST changes resulting in an alternation of high-density and low-density bands (HDB and LDB). Notably, growth rates and the timing of the HDBs and LDBs relative to the seasons differ on a global scale within geographic regions. In this contribution, we use combined information of skeletal density and seasonally resolved oxygen isotope SST estimates from massive Porites from a Late Miocene (9 Ma) reef in the eastern Mediterranean Sea (Crete, Greece) to understand reef vulnerability over short and geological periods of time. Three types of HDB–SST relationships have been found: (1) coincidence of HDB with summer, (2) winter or (3) autumn and spring. The latter doubles HDBs in a year and implies maximum calcification is coupled to the taxon-specific optimum SST during the transitional seasons and reduced at its respective critical winter and summer SSTs. Modeling with a nonlinear temperature–calcification relationship reproduces the climate barcode of density bands. The model should be relevant for other poikilothermic carbonate producers in reefs and platforms and has implications for judging geographic distributions and causes of extinctions of corals, benthic carbonate communities and entire carbonate systems. With regard to the causes underlying expansion and demise of carbonate platforms and reefs in geological history, we expect the model predictions to help for a deeper understanding of biotic responses during hyperthermals or coolings and possibly also for identifying regions in the modern ocean where corals are endangered or taking advantage of global warming. 相似文献
69.
70.
PYRABACTIN RESISTANCE1-LIKE8 Plays an Important Role for the Regulation of Abscisic Acid Signaling in Root 总被引:2,自引:0,他引:2