Data on annotation and analysis of genome sequence of Paenibacillus elgii YSY-1.2, a promising chitinase-producing, plant-growth-promoting, and biocontrol agent.

The bacterium Paenibacillus elgii YSY-1.2 was recently isolated from soil collected from Yok Don National Park in Vietnam. Previous experiments showed this bacterium possesses high chitin-degrading activity, plant-growth promotion, and biocontrol capacity. Here, we report the draft genome sequence of strain YSY-1.2 for further characterizations related to crop production. The genome sequencing was performed using the DNBSeq-G99 with the Illumina platform. The draft genome of P. elgii YSY-1.2 has 8,240,519 bp in length and comprises 135 contigs. It has an N50 of 315,408 bp and a GC% of 52.8%. The genome contains 7498 protein-coding genes, 87 tRNA genes, and 1 rRNA gene. Among the protein-coding sequences, 6610 were assigned by COG, while 3230 were assigned by KEGG. The genome possesses at least 61 genes involved in environmental adaptation and plant growth promotion. Additionally; there are 258 carbohydrate-active enzymes deduced from the genome; among them, at least 14 may contribute to the biocontrol capacity. The chitin-degrading system of strain YSY-1.2 contains 16 chitinolytic enzymes, comprising 10 chitinases, 4 ß-N-acetylhexosaminidases, and 2 auxiliary activities. Furthermore, 32 gene clusters encoding antimicrobial metabolites were identified from the genome, with 17 showing no sequence similarities to reported clusters. Data provide an insight into the genomic information of strain YSY-1.2 and could lead to valuable further explorations and applications in crop production. This is the first report describing the genome sequence of P. elgii isolated from Vietnam.

RsmD, a Chloroplast rRNA m2G Methyltransferase, Plays a Role in Cold Stress Tolerance by Possibly Affecting Chloroplast Translation in Arabidopsis.

Ribosomal RNA (rRNA) methylation is a pivotal process in the assembly and activity of ribosomes, which in turn play vital roles in the growth, development and stress responses of plants. Although few methyltransferases responsible for rRNA methylation have been identified in plant chloroplasts, the nature and function of these enzymes in chloroplasts remain largely unknown. In this study, we characterized ArabidopsisRsmD (At3g28460), an ortholog of the methyltransferase responsible for N2-methylguanosine (m2G) modification of 16S rRNA in Escherichia coli. Confocal microscopic analysis of an RsmD- green fluorescent protein fusion protein revealed that RsmD is localized to chloroplasts. Primer extension analysis indicated that RsmD is responsible for m2G methylation at position 915 in the 16S rRNA of Arabidopsis chloroplasts. Under cold stress, rsmd mutant plants exhibited retarded growth, i.e. had shorter roots, lower fresh weight and pale-green leaves, compared with wild-type (WT) plants. However, these phenotypes were not detected in response to drought or salt stress. Notably, the rsmd mutant was hypersensitive to erythromycin or lincomycin and accumulated fewer chloroplast proteins compared with the WT, suggesting that RsmD influences translation in chloroplasts. Complementation lines expressing RsmD in the rsmd mutant background recovered WT phenotypes. Importantly, RsmD harbored RNA methyltransferase activity. Collectively, the findings of this study indicate that RsmD is a chloroplast 16S rRNA methyltransferase responsible for m2G915 modification that plays a role in the adaptation of Arabidopsisto cold stress.

Functional Characterization of a Putative RNA Demethylase ALKBH6 in Arabidopsis Growth and Abiotic Stress Responses.

RNA methylation and demethylation, which is mediated by RNA methyltransferases (referred to as "writers") and demethylases (referred to as "erasers"), respectively, are emerging as a key regulatory process in plant development and stress responses. Although several studies have shown that AlkB homolog (ALKBH) proteins are potential RNA demethylases, the function of most ALKBHs is yet to be determined. The Arabidopsis thaliana genome contains thirteen genes encoding ALKBH proteins, the functions of which are largely unknown. In this study, we characterized the function of a potential eraser protein, ALKBH6 (At4g20350), during seed germination and seedling growth in Arabidopsis under abiotic stresses. The seeds of T-DNA insertion alkbh6 knockdown mutants germinated faster than the wild-type seeds under cold, salt, or abscisic acid (ABA) treatment conditions but not under dehydration stress conditions. Although no differences in seedling and root growth were observed between the alkbh6 mutant and wild-type under normal conditions, the alkbh6 mutant showed a much lower survival rate than the wild-type under salt, drought, or heat stress. Cotyledon greening of the alkbh6 mutants was much higher than that of the wild-type upon ABA application. Moreover, the transcript levels of ABA signaling-related genes, including ABI3 and ABI4, were down-regulated in the alkbh6 mutant compared to wild-type plants. Importantly, the ALKBH6 protein had an ability to bind to both m6A-labeled and m5C-labeled RNAs. Collectively, these results indicate that the potential eraser ALKBH6 plays important roles in seed germination, seedling growth, and survival of Arabidopsis under abiotic stresses.