Search results for "Regulator gene"

The targeted overexpression of SlCDF4 in the fruit enhances tomato size and yield involving gibberellin signalling

2020

AbstractTomato is one of the most widely cultivated vegetable crops and a model for studying fruit biology. Although several genes involved in the traits of fruit quality, development and size have been identified, little is known about the regulatory genes controlling its growth. In this study, we characterized the role of the tomato SlCDF4 gene in fruit development, a cycling DOF-type transcription factor highly expressed in fruits. The targeted overexpression of SlCDF4 gene in the fruit induced an increased yield based on a higher amount of both water and dry matter accumulated in the fruits. Accordingly, transcript levels of genes involved in water transport and cell division and expans…

2021

The scarcity of transcriptional regulatory genes in Buchnera aphidicola, an obligate endosymbiont in aphids, suggests the stability of expressed gene patterns and metabolic pathways. This observation argues in favor of the hypothesis that this endosymbiont bacteria might contribute little to the host adaptation when aphid hosts are facing challenging fluctuating environment. Finding evidence for the increased expression or silenced genes involved in metabolic pathways under the pressure of stress conditions and/or a given environment has been challenging for experimenters with this bacterial symbiotic model. Transcriptomic data have shown that Buchnera gene expression changes are confined t…

Constitutive activation of MexT by amino acid substitutions results in MexEF-OprN overproduction in clinical isolates of Pseudomonas aeruginosa

2018

ABSTRACT When overproduced, the multidrug efflux system MexEF-OprN increases the resistance of Pseudomonas aeruginosa to fluoroquinolones, chloramphenicol, and trimethoprim. In this work, we demonstrate that gain-of-function mutations in the regulatory gene mexT result in oligomerization of the LysR regulator MexT, constitutive upregulation of the efflux pump, and increased resistance in clinical isolates.

RBFOX1, encoding a splicing regulator, is a candidate gene for aggressive behavior

2020

The RBFOX1 gene (or A2BP1) encodes a splicing factor important for neuronal development that has been related to autism spectrum disorder and other neurodevelopmental phenotypes. Evidence from complementary sources suggests that this gene contributes to aggressive behavior. Suggestive associations with RBFOX1 have been identified in genome-wide association studies (GWAS) of anger, conduct disorder, and aggressive behavior. Nominal association signals in RBFOX1 were also found in an epigenome-wide association study (EWAS) of aggressive behavior. Also, variants in this gene affect temporal lobe volume, a brain area that is altered in several aggression-related phenotypes. In animals, this gen…

Perturbation of Developmental Regulatory Gene Expression by a G-Quadruplex DNA Inducer in the Sea Urchin Embryo.

2018

The G-quadruplex (G4) is a four-stranded DNA structure identified in vivo in guanine-rich regions located in the promoter of a number of genes. Intriguing evidence suggested that small molecules acting as G4-targeting ligands could potentially regulate multiple cellular processes via either stabilizing or disruptive effects on G4 motifs. Research in this field aims to prove the direct role of G4 ligands and/or structures on a specific biological process in a complex living organism. In this study, we evaluate in vivo the effects of a nickel(II)-salnaphen-like complex, named Nisaln, a potent G4 binder and stabilizer, during embryogenesis of the sea urchin embryo. We describe developmental de…

Complex Regulatory Networks Governing Production of the Glycopeptide A40926

2018

Glycopeptides (GPAs) are an important class of antibiotics, with vancomycin and teicoplanin being used in the last 40 years as drugs of last resort to treat infections caused by Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus. A few new GPAs have since reached the market. One of them is dalbavancin, a derivative of A40926 produced by the actinomycete Nonomuraea sp. ATCC 39727, recently classified as N. gerenzanensis. This review summarizes what we currently know on the multilevel regulatory processes governing production of the glycopeptide A40926 and the different approaches used to increase antibiotic yields. Some nutrients, e.g., valine, l-glutamine and mal…

A Two-Component regulatory system with opposite effects on glycopeptide antibiotic biosynthesis and resistance

2020

AbstractThe glycopeptide A40926, produced by the actinomycete Nonomuraea gerenzanensis, is the precursor of dalbavancin, a second-generation glycopeptide antibiotic approved for clinical use in the USA and Europe in 2014 and 2015, respectively. The final product of the biosynthetic pathway is an O-acetylated form of A40926 (acA40926). Glycopeptide biosynthesis in N. gerenzanensis is dependent upon the dbv gene cluster that encodes, in addition to the two essential positive regulators Dbv3 and Dbv4, the putative members of a two-component signal transduction system, specifically the response regulator Dbv6 and the sensor kinase Dbv22. The aim of this work was to assign a role to these two ge…

The transcriptional programme of contact-inhibition.

2010

Proliferation of non-transformed cells is regulated by cell-cell contacts, which are referred to as contact-inhibition. Vice versa, transformed cells are characterised by a loss of contact-inhibition. Despite its generally accepted importance for cell-cycle control, little is known about the intracellular signalling pathways involved in contact-inhibition. Unravelling the molecular mechanisms of contact-inhibition and its loss during tumourigenesis will be an important step towards the identification of novel target genes in tumour diagnosis and treatment. To better understand the underlying molecular mechanisms we identified the transcriptional programme of contact-inhibition in NIH3T3 fib…

Abdominal-A mediated repression of Cyclin E expression during cell-fate specification in the Drosophila central nervous system

2009

Homeotic/Hox genes are known to specify a given developmental pathway by regulating the expression of downstream effector genes. During embryonic CNS development of Drosophila, the Hox protein Abdominal-A (AbdA) is required for the specification of the abdominal NB6-4 lineage. It does so by down regulating the expression of the cell cycle regulator gene Dcyclin E (CycE). CycE is normally expressed in the thoracic NB6-4 lineage to give rise to mixed lineage of neurons and glia, while only glial cells are produced from the abdominal NB6-4 lineage due to the repression of CycE by AbdA. Here we investigate how AbdA represses the expression of CycE to define the abdominal fate of a single NB6-4 …

CtsR is the master regulator of stress response gene expression in Oenococcus oeni.

2005

ABSTRACT Although many stress response genes have been characterized in Oenococcus oeni , little is known about the regulation of stress response in this malolactic bacterium. The expression of eubacterial stress genes is controlled both positively and negatively at the transcriptional level. Overall, negative regulation of heat shock genes appears to be more widespread among gram-positive bacteria. We recently identified an ortholog of the ctsR gene in O. oeni . In Bacillus subtilis , CtsR negatively regulates expression of the clp genes, which belong to the class III family of heat shock genes. The ctsR gene of O. oeni is cotranscribed with the downstream clpC gene. Sequence analysis of t…