Search

Dimethylsulfoniopropionate (DMSP) is an abundant marine organosulfur compound with roles in stress protection, chemotaxis, nutrient and sulfur cycling and climate regulation. Here we report the discovery of a bifunctional DMSP biosynthesis enzyme, DsyGD, in the transamination pathway of the rhizobacterium Gynuella sunshinyii and some filamentous cyanobacteria not previously known to produce DMSP. DsyGD produces DMSP through its N-terminal DsyG methylthiohydroxybutyrate S-methyltransferase and C-terminal DsyD dimethylsulfoniohydroxybutyrate decarboxylase domains. Phylogenetically distinct DsyG-like proteins, termed DSYE, with methylthiohydroxybutyrate S-methyltransferase activity were found in diverse and environmentally abundant algae, comprising a mix of low, high and previously unknown DMSP producers. Algae containing DSYE, particularly bloom-forming Pelagophyceae species, were globally more abundant DMSP producers than those with previously described DMSP synthesis genes. This work greatly increases the number and diversity of predicted DMSP-producing organisms and highlights the importance of Pelagophyceae and other DSYE-containing algae in global DMSP production and sulfur cycling., (© 2024. The Author(s).)

The mitochondrial genome (mitogenome) plays an important role in revealing molecular evolution. In this study, the complete mitogenome of Grammodes geometrica (G. geometrica) (Lepidoptera: Erebidae) was sequenced and characterized. The nucleotide composition of the genome is highly A + T biased, accounting for 80.49%. Most protein-coding genes (PCGs) are initiated by ATN codons except for the cytochrome oxidase subunit 1 (cox1) gene, which was initiated by CGA. The order and orientation of genes with the order trnM-trnI-trnQ-nad2 is a typical rearrangement compared with those ancestral insects in which trnM is located between trnQ and nad2. Most tRNA genes were folded into the typical cloverleaf structure except for trnS1 (AGN). The A + T-rich region contains the conserved motif "ATAGA" followed by a 19 bp poly-T stretch, which was also observed in other Noctuoidea species. In addition, we reconstructed phylogenetic trees among the nucleotide alignments of five families of Noctuoidea species except the Oenosandridae. Finally, we achieved a well-supported tree, which showed that G. geometrica belongs to the Erebidae family. Moreover, the relationships at the family-level can be displayed as follows: (Notodontidae + (Erebidae + (Nolidae + (Euteliidae + Noctuidae))))., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In the present study, the complete mitochondrial genome (mitogenome) of Clostera anastomosis (C. anastomosis) has been determined for the first time. The mitogenome is 15,390 base pairs (bp) in length, comprised of 13 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and one non-coding control region (CR). The gene order shows a typical trnM rearrangement (trnM-trnI-trnQ) compared to ancestral insects (trnI-trnQ-trnM). Almost all the PCGs have the same start codon (ATN) except for cox1 (CGA), and almost all tRNAs have a typical cloverleaf secondary structure except for trnS1. At the beginning of the CR, we found a conserved motif "ATAGA + poly-T" as found in other lepidopteran insects. There are 20 intergenic regions and 11 overlapping regions, ranging from 1 to 53 bp and 1 to 9 bp, respectively. The A + T content is relatively high across the whole mitogenome. The optimal tree topologies of Noctuoidea were given by the dataset consisting of all 13 PCGs from five families (exclude Oenosandridae). Our trees suggested a topology of (Notodontidae + (Erebidae + (Nolidae + (Euteliidae + Noctuidae)))) and identified that C. anastomosis belongs to Notodontidae., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Small heat shock proteins (sHSPs) are conserved among insects and play an important role in the regulation of many biological processes, including temperature stress, abiotic stress, immune responses, metamorphosis, and embryo development. Antheraea pernyi is an economically valuable silk-producing moth and source of insect food containing high-quality protein. The aim of this study was to quantify expression of the ApsHSP21 gene in response to pathogen-associated molecular patterns (PAMPs) and nucleopolyhedrovirus (NPV) challenge. The deduced ApsHSP21 protein sequence consists of 186 residues with a calculated molecular mass of 21.0 kDa and an isoelectronic point (pI) of 6.63. The protein contains a conserved α-crystallin domain (ACD), and includes two casein kinase II phosphorylation sites, a protein kinase C phosphorylation site, two tyrosine kinase phosphorylation sites, and various polypeptide binding sites. Phylogenetic analysis revealed that ApsHSP21 is closely related to homologs from other insects. Real-time quantitative reverse transcription PCR (qRT-PCR) analysis revealed that expression of ApsHSP21 was significantly up-regulated at different timepoints following simulated pathogen challenge with lipopolysaccharide (LPS), peptidoglycan (PGN), glucan, and NPV. The results suggest sHSP21 is involved in innate immune responses in A. pernyi., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The mitochondrial genome (mitogenome) can provide information for phylogenetic analyses and evolutionary biology. We sequenced, annotated, and characterized the mitogenome of Euproctis similis. The complete mitogenome is 15,437bp in length, containing 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and a control region (A+T-rich region). The A+T content in the mitogenome was 80.16%. All PCGs use standard ATN as a start codon, with the exception of cytochrome c coxidase 1 (cox1) with CGA. A gene rearrangement (trnM) was found. All transfer RNA (tRNA) genes have a typical clover-leaf structure except for trnS1 (AGN). Phylogenetic analysis was performed using Bayesian Inference and Maximum Likelihood based on the amino acid and nucleotide sequences of 13 mitochondrial PCGs. The well-supported phylogenetic relationships can be generally described as: Notodontidae+(Erebidae+(Nolidae+(Euteliidae+Noctuidae))). The tree support that E. similis shares a close ancestry with Erebidae insects. Our results indicate that Erebidae is a sister group to the other families (Euteliidae, Nolidae, and Noctuidae)., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The mitochondrial genome (mt genome) provides important information for understanding molecular evolution and phylogenetics. As such, the two complete mt genomes of Ampelophaga rubiginosa and Rondotia menciana were sequenced and annotated. The two circular genomes of A. rubiginosa and R. menciana are 15,282 and 15,636 bp long, respectively, including 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and an A + T-rich region. The nucleotide composition of the A. rubiginosa mt genome is A + T rich (81.5%) but is lower than that of R. menciana (82.2%). The AT skew is slightly positive and the GC skew is negative in these two mt genomes. Except for cox1, which started with CGA, all other 12PCGs started with ATN codons. The A + T-rich regions of A. rubiginosa and R. menciana were 399 bp and 604 bp long and consist of several features common to Bombycoidea insects. The order and orientation of A. rubiginosa and R. menciana mitogenomes with the order trnM-trnI-trnQ-nad2 is different from the ancestral insects in which trnM is located between trnQ and nad2 (trnI-trnQ-trnM-nad2). Phylogenetic analyses indicate that A. rubiginosa belongs in the Sphingidae family, and R. menciana belongs in the Bombycidae family.

In this study, the complete mitochondrial genome (mitogenome) of Clostera anachoreta (Lepidoptera: Notodontidae) was sequenced. It comprises 15,456 base pairs (bp), including 13 protein-coding genes (PCGs), two ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and one non-coding control region (CR), as found in other lepidopterans. Gene order is identical to that of typical lepidopterans. There are 15 intergenic spacers ranging from 2 to 49bp, and 9 overlapping regions ranging from 1 to 8bp, occurring throughout the genome. The CR is 347bp long. All PCGs are initiated by ATN codons. We found a typical gene rearrangement in C. anachoreta (tRNA Met -tRNA Ile -tRNA Gln ), which is different from ancestral insects (tRNA Ile -tRNA Gln -tRNA Met ). The gene rearrangement can be explained by a duplication/random loss model. Phylogenetic analyses indicate that C. anachoreta belongs to Notodontidae, and that the monophyly of Lepidopteran families is well supported., (Copyright © 2017. Published by Elsevier Inc.)

Gene arrangements in the mitochondrial genomes (mitogenomes) of insects are conserved across the major lineages, but can be rearranged within derived groups and may provide valuable phylogenetic characters. In this study, we sequenced the entire mitogenome of Parasa consocia , a moth of the family Limacodidae (Lepidoptera: Zygaenoidea). Compared with other lepidopterans and ancestral insects, the P. consocia mitogenome features a transfer RNA gene arrangement novel among lepidopterans between the ND3 and ND5 genes: RANSE F (the underline signifies an inverted gene), which differs from the ARNSE F arrangement of ancestral insects. This rearrangement can be explained by the tandem duplication-random loss model. We inferred a phylogenetic hypothesis for the lepidopteran superfamily based on mitochondrial amino-acid sequences using the Bayesian-inference and maximum-likelihood methods. Our results showed that P. consocia belongs to the Zygaenoidea superfamily and supported the following phylogenetic relationship: Yponomeutoidea + (Tortricoidea + Zygaenoidea + (Papilionoidea + (Pyraloidea + (Noctuoidea + (Geometroidea + Bombycoidea)))))). Comparative analyses indicated that mitogenomes are a useful phylogenetic tool at the subfamily level within the order Lepidoptera. Our findings also suggest that mitogenomes are likely to represent a valuable tool for systematics in other groups of lepidopterans. [ABSTRACT FROM AUTHOR]

The mitochondrial genome (mitogenome) provides important information for phylogenetic analysis and understanding evolutionary origins. Herein, we sequenced, annotated, and characterised the mitogenome of the crab Helice wuana to better understand its molecular evolution and phylogeny. The 16,359 bp mitogenome includes 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes and one control region. The genome composition is highly A + T biased 68.42%, and exhibits a negative AT–skew (− 0.036) and GC–skew (− 0.269) among Brachyura crabs. Gene rearrangements were detected, as was tandem duplication followed by random loss, which explains the translocation of mitochondrial genes. Phylogenetic analysis showed that H . wuana and H. tientsinensis clustered on one branch with high nodal support values. These results confirm that the placement of H . wuana within the Varunidae family of Thoracotrematan crabs. This study will provided a better understanding for gene rearrangements and crab evolution in the further. [ABSTRACT FROM AUTHOR]