The growth of all methanogens is limited to a specific temperature range. However, Methanothermobacter thermautotrophicus can be found in a variety of natural and artificial environments, the temperatures of which sometimes even exceed the temperature growth ranges of thermophiles. As a result, the extent to which methane production and survival are affected by temperature remains unclear. To investigate the mechanisms of methanogenesis that Archaea have evolved to cope with drastic temperature shifts, the responses of Methanothermobacter thermautotrophicus to temperature were investigated under a high temperature growth (71°C) and cold shock (4°C) using Isobaric tags for relative and absolute quantitation (iTRAQ). The results showed that methane formation is decreased and that protein folding and degradation are increased in both high‐ and low‐temperature treatments. In addition, proteins predicted to be involved in processing environmental information processing and in cell membrane/wall/envelope biogenesis may play key roles in affecting methane formation and enhancing the response of M. thermautotrophicus to temperature stress. Analysis of the genomic locations of the genes corresponding to these temperature‐dependent proteins predicted that 77 of the genes likely to form 32 gene clusters. Here, we assess the response of M. thermautotrophicus to different temperatures and provide a new level of understanding of methane formation and cellular putative adaptive responses.

This study was the first report about the complete chloroplast genome of Plantago fengdouensis (Plantaginaceae). The circular whole cp genome of P. fengdouensis was in a total length 164,976 bp with the typical quadripartite structure of angiosperms, containing two inverted repeats (IRs) of 38,644 bp separated by a large single-copy (LSC) region and a small single-copy (SSC) region of 82,972 and 4716 bp, respectively. The plastid genome of P. fengdouensis contains 113 genes, including 79 protein-coding genes, 4 ribosomal RNA genes, and 30 transfer RNA genes. The overall GC content of P. fengdouensis plastid genome is 38.0% and the corresponding values in LSC, SSC, and IR regions are 36.6, 30.2, and39.9%, respectively.

Curcuma alismatifolia, a bulbous flower known for its showy bracts, is widely used around the world as a cut flower, potted, and garden plant. Besides its ornamental value, this species is rich in terpenoid metabolites and could serve as a resource for essential oils. Here, we report a chromosome-level genome assembly of C. alismatifolia and describe its biosynthetic pathways for anthocyanins and terpenoids. This high-quality, assembled genome size is 991.3 Mb with a scaffold N50 value of 56.7 Mb. Evolutionary analysis of the genome suggests that C. alismatifolia diverged from Zingiber officinale about 9.7 million years ago, after it underwent a whole-genome duplication. Transcriptome analysis was performed on bracts at five developmental stages. Nine highly expressed genes were identified, encoding for six enzymes downstream of the anthocyanin biosynthetic pathway. Of these, one gene encoding F3′5′H might be a key node in the regulation of bract color formation. Co-expression network analysis showed that MYB, bHLH, NAC, and ERF transcription factors collectively regulated color formation in the bracts. Characterization of terpenoid biosynthesis genes revealed their dispersal and tandem duplications, both of which contributed greatly to the increase in the number of terpene synthase genes in C. alismatifolia, especially to species-specific expansion of sesquiterpene synthase genes. This work facilitates understanding of genetic basis of anthocyanin and terpenoid biosynthesis and could accelerate the selective breeding of C. alismatifolia varieties with higher ornamental and medicinal value.

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ABSTRACT. Castanopsis eyrei (Fagaceae) is one of the dominant tree species in mid-subtropical, evergreen, broad-leaved forests. We obtained 14 pairs of simple sequence repeat (SSR) primers from previous studies, which were used to analyze 90 C. eyrei individuals from three populations at different altitudes. Low heterozygosity was detected (F is = 0.6124), and the observed heterozygosity was lower than the expected heterozygosity, possibly because of inbreeding and/ or the population substructure. The genetic differentiation between populations was relatively low (F st = 0.0645); only 7% of the total genetic variation occurred between populations. The medium-altitude population had higher genetic diversity than the low-altitude or highaltitude populations.