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Simple Summary: Global climate change is a growing threat to the lives and ranges of reptile species. The present study examines three lizard species (Calotes versicolor, Ateuchosaurus chinensis, and Hemidactylus bowringii) that share a sympatric distribution in the Guangzhou region of Guangdong, China. Mitochondria act as energy-producing centers, and the present study analyses the effects of low temperatures in the context of warm winters on lizards, by examining their responses to low-temperature stress at the level of mitochondrial gene expression. This present study analyses the effects of low temperatures in the context of warm winters on the mitochondrial gene expression of lizards and reveals the implications of the distribution within it. Ecological factors related to climate extremes have a significant influence on the adaptability of organisms, especially for ectotherms such as reptiles that are sensitive to temperature change. Climate extremes can seriously affect the survival and internal physiology of lizards, sometimes even resulting in the loss of local populations or even complete extinction. Indeed, studies have shown that the expression levels of the nuclear genes and mitochondrial genomes of reptiles change under low-temperature stress. At present, the temperature adaptability of reptiles has rarely been studied at the mitochondrial genome level. In the present study, the mitochondrial genomes of three species of lizards, Calotes versicolor, Ateuchosaurus chinensis, and Hemidactylus bowringii, which live in regions of sympatry, were sequenced. We used RT-qPCR to explore the level of mitochondrial gene expression under low-temperature stress, as compared to a control temperature. Among the 13 protein-coding genes (PCGs), the steady-state transcript levels of ND4L, ND1, ATP6, and COII were reduced to levels of 0.61 ± 0.06, 0.50 ± 0.08, 0.44 ± 0.16, and 0.41 ± 0.09 in C. versicolor, respectively, compared with controls. The transcript levels of the ND3 and ND6 genes fell to levels of just 0.72 ± 0.05 and 0.67 ± 0.05 in H. bowringii, compared with controls. However, the transcript levels of ND3, ND5, ND6, ATP6, ATP8, Cytb, and COIII genes increased to 1.97 ± 0.15, 2.94 ± 0.43, 1.66 ± 0.07, 1.59 ± 0.17, 1.46 ± 0.04, 1.70 ± 0.16, and 1.83 ± 0.07 in A. chinensis. Therefore, the differences in mitochondrial gene expression may be internally related to the adaptative strategy of the three species under low-temperature stress, indicating that low-temperature environments have a greater impact on A. chinensis, with a small distribution area. In extreme environments, the regulatory trend of mitochondrial gene expression in reptiles is associated with their ability to adapt to extreme climates, which means differential mitochondrial genome expression can be used to explore the response of different lizards in the same region to low temperatures. Our experiment aims to provide one new research method to evaluate the potential extinction of reptile species in warm winter climates. [ABSTRACT FROM AUTHOR]

Although Catalpa bungei is a forest plant with considerable economic and ornamental value in China, its wood and decorative qualities are constrained by insect pests such as the shoot borer Omphisa plagialis (Lepidoptera). Overexpressing insect resistance genes such as crystal genes to develop an insect-resistant variety of C. bungei is an environmental and ecological approach. However, genotype limitations and low regeneration rates of embryogenic calli (EC) inhibit the development of transformation and the insect-resistant gene expression system in C. bungei. Here, we first established embryogenic callus induction and regeneration systems of five genotypes using mature seed and stem segment explants; the highest induction and regeneration rates of EC were 39.89 and 100%, respectively. Next, an efficient and stable Agrobacterium -mediated genetic transformation system was developed from EC and its positive frequency was up to 92.31%. Finally, using the transformation system, 15 and 22 transgenic C. bungei lines that expressed Cry2A and Cry9Aa-like were generated, respectively. These transgenic lines that exhibited significantly higher resistance to O. plagialis in the laboratory and field have great promise for meeting the challenge of future pest management under changing climatic conditions. Additionally, this efficient, fast, and stable transformation system could be a potential tool for gene function analysis and forest tree genetic improvement. [ABSTRACT FROM AUTHOR]

Clematis apiifolia, belonging to the Clematis L., is a woody vine native to China. It is characterized as heat resistant and fast growing. To better understand potential mechanisms involved in heat-stress responses in Clematis, we characterized the digital gene expression signatures of C. apiifolia under heat-stress conditions. Using RNA sequencing technology, we sequenced six libraries, three biological replicates of control samples and three of heat-stressed samples. In total, 61,708 unigenes were obtained, 36,447 (59.06%) of which were annotated. There were 1941 differentially expressed genes (DEGs) under heat stress, including 867 upregulated and 1074 downregulated genes. Gene ontology enrichment of DEGs revealed that 'metabolic process,' 'cellular process,' and 'single organism' were the top three functional terms under heat stress. A Kyoto Encyclopedia of Genes and Genomes analysis led to the identification of 'protein processing in metabolic pathways,' 'phenylpropanoid biosynthesis,' and 'biosynthesis of secondary metabolites' as significantly enriched pathways. Among the upregulated genes, heat-shock factors and heat-shock proteins, especially small heat-shock proteins, were particularly abundant under heat stress. The data will aid in elucidating the molecular events underlying heat-stress responses in Clematis L. [ABSTRACT FROM AUTHOR]

In addition to preventing precocious larval metamorphosis, juvenile hormone (JH), synthesized in corpora allata (CA), is known to stimulate female reproduction of insects. JH titer is extremely low or absent during metamorphosis, but thereafter rapidly increases in the previtellogenic stage and rises to a peak in the vitellogenic phase. However, the mechanisms underlying the biosynthesis of high levels of JH in adults remain unclear. We found in this study that 12 genes involved in JH synthesis pathway were highly expressed in the CA of adult locusts. By transcriptome analysis and quantitative real‐time – polymerase chain reaction validation, a total of 106 evolutionary conserved micro RNAs (miRNAs) and 163 species‐specific miRNAs were identified in locust CA. Dual‐luciferase assay revealed that 17 miRNAs bound to 10 JH synthesis genes (JHSGs) and downregulated their expression. These miRNAs were expressed in low levels during vitellogenic stage, which was oppositive from that of targeting JHSGs. Six miRNAs including miR‐971‐3p, miR‐31a, miR‐9‐5p, miR‐1‐3p, miR‐315, and miR‐282 were selected for function study. Co‐application of agomiRs resulted in significantly decreased levels of targeting JHSGs, accompanied by significantly reduced vitellogenin expression as well as arrested ovarian development. The data suggest that multiple miRNAs expressed synchronously at low levels in the vitellogenic phase, thereby ensuring the high levels of JHSG expression to facilitate JH biosynthesis required for JH‐dependent female reproduction. The findings provide important information for deciphering miRNA—messenger RNA modules for JH biosynthesis as well as JH regulation of insect metamorphosis and reproduction. [ABSTRACT FROM AUTHOR]

Genomic imprinting is an epigenetic phenomenon that causes genes to be differentially expressed depending on their parent of origin. To evaluate the evolutionary conservation of genomic imprinting and the effects of ploidy on this process, we investigated parent-of-origin-specific gene expression patterns in the endosperm of diploid (Aegilops spp), tetraploid, and hexaploid wheat (Triticum spp) at various stages of development via high-throughput transcriptome sequencing. We identified 91, 135, and 146 maternally or paternally expressed genes (MEGs or PEGs, respectively) in diploid, tetraploid, and hexaploid wheat, respectively, 52.7% of which exhibited dynamic expression patterns at different developmental stages. Gene Ontology enrichment analysis suggested that MEGs and PEGs were involved in metabolic processes and DNA-dependent transcription, respectively. Nearly half of the imprinted genes exhibited conserved expression patterns during wheat hexaploidization. In addition, 40% of the homoeolog pairs originating from whole-genome duplication were consistently maternally or paternally biased in the different subgenomes of hexaploid wheat. Furthermore, imprinted expression was found for 41.2% and 50.0% of homolog pairs that evolved by tandem duplication after genome duplication in tetraploid and hexaploid wheat, respectively. These results suggest that genomic imprinting was evolutionarily conserved between closely related Triticum and Aegilops species and in the face of polyploid hybridization between species in these genera. [ABSTRACT FROM AUTHOR]

Rich flower colors are valuable attributes for Lagerstroemia indica ornamental industry. To gain insights into the regulatory network controlling flower color formation and identify the key regulatory genes, in this study, we comprehensively analyzed the metabolome and transcriptome of three L. indica cultivars at the full bloom stage: red Dynamite, purple Lanmaizi, and white Yuzhuafendie. A total of 111 potential anthocyanin biosynthetic structural genes were screened and assigned among the 24 chromosomes. Significant up-accumulation of cyanidins in cv. Dynamite and petunidins in cv. Lanmaizi confer to them different flower colors. LiANS and LiOMT28 , two structural genes, may work in tandem with transcription factors (TFs) from the MYB, bHLH, WDR, G2-like, ERF, WRKY, bZIP, and E2F/DP families to modulate color formation in L. indica petals, according to correlation tests of anthocyanin levels and transcriptional changes. Subsequent research confirmed the positive correlation between petal colorating processes and the transcripts of LiANS. Increased anthocyanin accumulation in leaves and petals, pale pink flower color, up-regulation of LiF3H1 , LiF3H2 , LiDFR , LiOMT29 , and Lind24G0871 (R2R3 MYB), and down-regulation of Lind04G0622 (R2R3 MYB) were also observed in the LiANS -overexpressing shoots. These findings suggest that LiANS may assemble molecular modules with these structural genes and MYB TFs to participate in anthocyanin biosynthesis in L. indica. Further research on the intricate physiological processes and molecular mechanisms connected to the flower color and its regulatory networks in L. indica may benefit from the novel insights gained from the study. • Cyanidins were enriched in red petals, while petunidins were enriched in purple. • Anthocyanin biosynthetic structural genes were first identified in the L. indica. • LiANS overexpressing changed the petals from white to pale pink hue. [ABSTRACT FROM AUTHOR]