With global warming as a major environment concern over the coming years, heat tolerance is an important trait for forest tree survival during the predicted future warmer weather conditions. Cryptomeria japonica is a coniferous species widely distributed throughout Japan, and thus, can adapt to a wide range of air temperatures. To elucidate genes involved in heat response in Cryptomeria japonica, transcriptome analysis was conducted for seedlings under heat shock conditions. To test whether heat acclimation affects levels of gene expression, half of the seedlings were pretreated with moderately high temperatures prior to heat shock. De novo assembly of the transcriptome generated 107,924 unigenes and the analysis of differentially expressed genes was conducted using these unigenes. A total of 5217 differentially expressed genes were identified. Most genes upregulated by heat shock, regardless of pre-heat treatment, were conserved to heat response genes of angiosperm species, such as heat shock factors (Hsf) and heat shock proteins (Hsp). Pre-heating of seedlings affected expression levels of several Hsfs and their induction was lower in pre-heated seedlings than in seedlings without pre-heat treatment. This suggests a conserved role of Hsfs in heat response and heat acclimation in seed plants. On the other hand, many unknown genes were upregulated in only seedlings without pre-heat treatment after heat exposure. Notably, expression of gypsy/Ty3 type retrotransposons was dramatically induced. These findings provide valuable information to develop a better understanding of the molecular mechanisms of heat response and acclimation in C. japonica.

随着未来几年全球变暖成为主要的环境问题，在预计的未来变暖天气条件下，耐热性是林木生存的重要特征。日本柳杉是在日本广泛分布的一种针叶树种，因此可以适应各种气温。阐明参与日本柳杉热响应的基因，在热激条件下对幼苗进行转录组分析。为了测试热适应是否影响基因表达水平，将一半的幼苗在热激之前用中等高温进行了预处理。转录组的从头组装产生107,924个单基因，并使用这些单基因进行差异表达基因的分析。总共鉴定了5217个差异表达基因。无论是否进行了预处理，大多数通过热激而上调的基因都被保留在被子植物的热响应基因中，例如热激因子（Hsf）和热激蛋白（Hsp）。幼苗的预热影响了几种Hsfs的表达水平，预诱导的幼苗的诱导程度要低于未进行预热处理的幼苗。这表明Hsfs在种子植物的热响应和热适应中的保守作用。另一方面，许多未知基因仅在暴露于热后未进行预处理的幼苗中上调。明显地，吉普赛/ Ty3型逆转座子的表达被显着诱导。这些发现提供了宝贵的信息，可以帮助人们更好地了解热响应和适应的分子机制。蚕蛾。