MusaDREB1G-Like Protein Modulates Cold and Drought Tolerance in Musa x paradisica.

MusaDREB1G acts as an abiotic stress responsive transcription factor that modulates drought or cold stress tolerance in through multifaceted mechanisms. This study paves the way for engineering stress‐resistant banana crops using MusaDREB1G.

Human TLS DNA polymerase: saviors or threats under replication stress?

The maintenance of genomic stability is crucial for life, threatened by DNA damage from both endogenous and exogenous sources. Cells employ DNA damage response through various repair mechanisms and DNA damage tolerance via translesion synthesis (TLS), to bypass DNA lesions and prevent replication fork collapse. This review explores the roles of human TLS polymerases in navigating replication stress, a critical process that can lead to genomic instability and cancer.

Surviving the storm: exploring the role of natural transformation in nutrition and DNA repair of stressed .

, a natural transformation (NT)-enabled bacterium renowned for its exceptional radiation resistance, employs unique DNA repair and oxidative stress mitigation mechanisms as a strategic response to DNA damage. This study excavates into the intricate roles of NT machinery in the stressed , focusing on the genes , , , , and , which are instrumental in the uptake and processing of extracellular DNA (eDNA). Our data reveal that NT not only supports the nutritional needs of under stress but also has roles in DNA repair.

A perspective on tumor radiation resistance following high-LET radiation treatment.

High-linear energy transfer (LET) radiation is a promising alternative to conventional low-LET radiation for therapeutic gain against cancer owing to its ability to induce complex and clustered DNA lesions. However, the development of radiation resistance poses a significant barrier. The potential molecular mechanisms that could confer resistance development are translesion synthesis (TLS), replication gap suppression (RGS) mechanisms, autophagy, epithelial-mesenchymal transition (EMT) activation, release of exosomes, and epigenetic changes.

DNA damage response and cell cycle regulation in bacteria: a twist around the paradigm.

The co-protease activity in the RecA-ssDNA complex cleaves the autorepressor LexA, resulting in the derepression of a large number of genes under LexA control. This process is called the SOS response, and genes that are expressed in response to DNA damage are called SOS genes. The proteins encoded by the SOS genes are involved in both DNA repair and maintaining the functions of crucial cell division proteins (e.

Multitasking functions of bacterial extracellular DNA in biofilms.

Bacterial biofilms are intricate ecosystems of microbial communities that adhere to various surfaces and are enveloped by an extracellular matrix composed of polymeric substances. Within the context of bacterial biofilms, extracellular DNA (eDNA) originates from cell lysis or is actively secreted, where it exerts a significant influence on the formation, stability, and resistance of biofilms to environmental stressors. The exploration of eDNA within bacterial biofilms holds paramount importance in research, with far-reaching implications for both human health and the environment.

Natural transformation-specific DprA coordinate DNA double-strand break repair pathways in heavily irradiated .

exhibits remarkable survival under extreme conditions, including ionizing radiation, desiccation, and various DNA-damaging agents. It employs unique repair mechanisms, such as single-strand annealing (SSA) and extended synthesis-dependent strand annealing (ESDSA), to efficiently restore damaged genome. In this study, we investigate the role of the natural transformation-specific protein DprA in DNA repair pathways following acute gamma radiation exposure.

Biochemical Properties and Roles of DprA Protein in Bacterial Natural Transformation, Virulence, and Pilin Variation.

Natural transformation enables bacteria to acquire DNA from the environment and contributes to genetic diversity, DNA repair, and nutritional requirements. DNA processing protein A (DprA) receives incoming single-stranded DNA and assists RecA loading for homology-directed natural chromosomal transformation and DNA strand annealing during plasmid transformation. The gene occurs in the genomes of all known bacteria, irrespective of their natural transformation status.

Characterization of DNA Processing Protein A (DprA) of the Radiation-Resistant Bacterium Deinococcus radiodurans.

Environmental DNA uptake by certain bacteria and its integration into their genome create genetic diversity and new phenotypes. DNA processing protein A (DprA) is part of a multiprotein complex and facilitates the natural transformation (NT) phenotype in most bacteria. Deinococcus radiodurans, an extremely radioresistant bacterium, is efficient in NT, and its genome encodes nearly all of the components of the natural competence complex.

Involvement of serine / threonine protein kinases in DNA damage response and cell division in bacteria.

The roles of Serine/Threonine protein kinases (STPKs) in bacterial physiology, including bacterial responses to nutritional stresses and under pathogenesis have been well documented. STPKs roles in bacterial cell cycle regulation and DNA damage response have not been much emphasized, possibly because the LexA/RecA type SOS response became the synonym to DNA damage response and cell cycle regulation in bacteria. This review summarizes current knowledge of STPKs genetics, domain organization, and their roles in DNA damage response and cell division regulation in bacteria.

PprA Protein Inhibits DNA Strand Exchange and ATP Hydrolysis of RecA and Regulates the Recombination in Gamma-Irradiated Cells.

DrRecA and PprA proteins function are crucial for the extraordinary resistance to γ-radiation and DNA strand break repair in . DrRecA mediated homologous recombination help in DNA strand break repair and cell survival, while the PprA protein confers radio-resistance its roles in DNA repair, genome maintenance, and cell division. Genetically and genes interact and constitute an epistatic group however, the mechanism underlying their functional interaction is not clear.

WD40 domain of RqkA regulates its kinase activity and role in extraordinary radioresistance of .

RqkA, a DNA damage responsive serine/threonine kinase, is characterized for its role in DNA repair and cell division in . It has a unique combination of a kinase domain at N-terminus and a WD40 type domain at C-terminus joined through a linker. WD40 domain is comprised of eight β-propeller repeats held together via 'tryptophan-docking motifs' and forming a typical 'velcro' closure structure.

MusaMPK5, a mitogen activated protein kinase is involved in regulation of cold tolerance in banana.

Mitogen activated protein kinases (MAPKs) are known to play important functions in stress responses of plants. We have functionally characterized a MAPK, MusaMPK5 from banana and demonstrated its function in cold tolerance response of banana plants. Expression of MusaMPK5 showed positive response to cold, methyl-jasmonate and salicylic acid treatment.

Phosphorylation of deinococcal RecA affects its structural and functional dynamics implicated for its roles in radioresistance of .

Deinococcus RecA (DrRecA) protein is a key repair enzyme and contributes to efficient DNA repair of . Phosphorylation of DrRecA at Y77 (tyrosine 77) and T318 (threonine 318) residues modifies the structural and conformational switching that impart the efficiency and activity of DrRecA. Dynamics comparisons of DrRecA with its phosphorylated analogues support the idea that phosphorylation of Y77 and T318 sites could change the dynamics and conformation plasticity of DrRecA.

Phosphorylation of FtsZ and FtsA by a DNA Damage-Responsive Ser/Thr Protein Kinase Affects Their Functional Interactions in .

, a highly radioresistant bacterium, does not show LexA-dependent regulation of expression in response to DNA damage. On the other hand, phosphorylation of DNA repair proteins such as PprA and RecA by a DNA damage-responsive Ser/Thr protein kinase (STPK) (RqkA) could improve their DNA metabolic activities as well as their roles in the radioresistance of Here we report RqkA-mediated phosphorylation of cell division proteins FtsZ and FtsA and in surrogate bacteria expressing RqkA. Mass spectrometric analysis mapped serine 235 and serine 335 in FtsZ and threonine 272, serine 370, and serine 386 in FtsA as potential phosphorylation sites.

drFrnE Represents a Hitherto Unknown Class of Eubacterial Cytoplasmic Disulfide Oxido-Reductases.

Aims: Living cells employ thioredoxin and glutaredoxin disulfide oxido-reductases to protect thiol groups in intracellular proteins. FrnE protein of Deinococcus radiodurans (drFrnE) is a disulfide oxido-reductase that is induced in response to Cd exposure and is involved in cadmium and radiation tolerance. The aim of this study is to probe structure, function, and cellular localization of FrnE class of proteins.

Studies of protein-protein interactions in Fanconi anemia pathway to unravel the DNA interstrand crosslink repair mechanism.

Fanconi anemia (FA), a cancer predisposition syndrome exhibits hallmark feature of radial chromosome formation, and hypersensitivity to DNA crosslinking agents. A set of FA pathway proteins mainly FANCI, FANCD2 and BRCA2 are expressed to repair the covalent crosslink between the dsDNA. However, FA, BRCA pathways play an important role in DNA ICL repair as well as in homologous recombination repair, but the presumptive role of FA-BRCA proteins has not clearly explored particularly in context to function associated protein-protein interactions (PPIs).

Structural and biophysical properties of h-FANCI ARM repeat protein.

Fanconi anemia complementation groups - I (FANCI) protein facilitates DNA ICL (Inter-Cross-link) repair and plays a crucial role in genomic integrity. FANCI is a 1328 amino acids protein which contains armadillo (ARM) repeats and EDGE motif at the C-terminus. ARM repeats are functionally diverse and evolutionarily conserved domain that plays a pivotal role in protein-protein and protein-DNA interactions.

Phosphorylation of Deinococcus radiodurans RecA Regulates Its Activity and May Contribute to Radioresistance.

Deinococcus radiodurans has a remarkable capacity to survive exposure to extreme levels of radiation that cause hundreds of DNA double strand breaks (DSBs). DSB repair in this bacterium depends on its recombinase A protein (DrRecA). DrRecA plays a pivotal role in both extended synthesis-dependent strand annealing and slow crossover events of DSB repair during the organism's recovery from DNA damage.

DNA Gyrase of Deinococcus radiodurans is characterized as Type II bacterial topoisomerase and its activity is differentially regulated by PprA in vitro.

The multipartite genome of Deinococcus radiodurans forms toroidal structure. It encodes topoisomerase IB and both the subunits of DNA gyrase (DrGyr) while lacks other bacterial topoisomerases. Recently, PprA a pleiotropic protein involved in radiation resistance in D.

Structure-function study of deinococcal serine/threonine protein kinase implicates its kinase activity and DNA repair protein phosphorylation roles in radioresistance of Deinococcus radiodurans.

The DR2518 (RqkA) a eukaryotic type serine/threonine protein kinase in Deinococcus radiodurans was characterized for its role in bacterial response to oxidative stress and DNA damage. The K42A, S162A, T169A and S171A mutation in RqkA differentially affected its kinase activity and functional complementation for γ radiation resistance in Δdr2518 mutant. For example, K42A mutant was completely inactive and showed no complementation while S171A, T169A and T169A/S171A mutants were less active and complemented proportionally to different levels as compared to wild type.

DR1769, a protein with N-terminal beta propeller repeats and a low-complexity hydrophilic tail, plays a role in desiccation tolerance of Deinococcus radiodurans.

The Deinococcus radiodurans genome encodes five putative quinoproteins. Among these, the Δdr2518 and Δdr1769 mutants became sensitive to gamma radiation. DR2518 with beta propeller repeats in the C-terminal domain was characterized as a radiation-responsive serine/threonine protein kinase in this bacterium.

Pyrroloquinoline quinone and a quinoprotein kinase support γ-radiation resistance in Deinococcus radiodurans and regulate gene expression.

Deinococcus radiodurans is known for its extraordinary resistance to various DNA damaging agents including γ-radiation and desiccation. The pqqE:cat and Δdr2518 mutants making these cells devoid of pyrroloquinoline quinone (PQQ) and a PQQ inducible Ser/Thr protein kinase, respectively, became sensitive to γ-radiation. Transcriptome analysis of these mutants showed differential expression of the genes including those play roles in oxidative stress tolerance and (DSB) repair in D.

Characterization of the role of the RadS/RadR two-component system in the radiation resistance of Deinococcus radiodurans.

Deinococcus radiodurans shows extraordinary tolerance to DNA damage, and exhibits differential gene expression and protein recycling. A putative response regulator, the DRB0091 (RadR) ORF, was identified from a pool of DNA-binding proteins induced in response to gamma radiation in this bacterium. radR is located upstream of drB0090, which encodes a putative sensor histidine kinase (RadS) on the megaplasmid.