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Camellia oleiferaAbel., belonging to the genus Camelliaof Theaceae, has been widely used as a cooking oil, lubricant, and in cosmetics. Because of complicated polyploidization and large genomes, reference genome information is still lacking. Systematic characterization of gene models based on transcriptome data is a fast and economical approach for C. oleifera. Pacific Biosciences single-molecule long-read isoform sequencing (Iso-Seq) and Illumina RNA-Seq combined with gas chromatography were performed for exploration of oil biosynthesis, accumulation, and comprehensive transcriptome analysis in C. oleiferaseeds at five different developmental stages. We report the first full-length transcriptome data set of C. oleiferaseeds comprising 40,143 deredundant high-quality isoforms. Among these isoforms, 37,982 were functionally annotated, and 271 (2.43%) belonged to fatty acid metabolism. A total of 8,344 full-length unique transcript models were obtained, and 8,151 (97.69%) of them produced more than two isoforms, suggesting a high degree of transcriptome complexity in C. oleiferaseeds. A total of 783 alternative splicing (AS) events were identified, among which the retained intron was the most abundant. We also obtained 1,910 long noncoding RNAs (lncRNAs) and found that AS events occurred in these lncRNAs. Potential transcript variants of genes involved in oil biosynthesis were also investigated. After performing weighted correlation network analysis, we found seven “gene modules” and hub genes for each module showing a significant association with oil content. The series test of clusters classified these modules into four significant profiles based on gene expression patterns. Protein–protein interaction network analysis showed that upregulated WRI1interacted with 17 genes encoding the enzymes playing key roles in oil synthesis. MYBand ZIPtranscriptional factors also showed significant interactions with key genes involved in oil synthesis. Collectively, our data advance the knowledge of RNA isoform diversity in seeds at different developmental stages and provide a rich resource for functional studies on oil synthesis in C. oleifera.

Transgenerational effects of microcystin-LR (MC-LR) released by cyanobacterial blooms have become a hot topic. In the present study, adult zebrafish pairs were exposed to 0, 0.4, 2, and 10 μg/L MC-LR for 60 days and the embryos (F1 generation) were hatched without or with continued MC-LR exposures at the same concentrations until 5 days postfertilization (dpf). The results showed the existence of MC-LR both in F0 gonads and in F1 embryos and indicated that MC-LR could be transferred directly from the F0 adult fish to F1 offspring. The adverse effects on sex hormone levels, sexual development, and fecundity in F0 generation along with abnormal development in F1 offspring were observed. Furthermore, downregulation of antioxidant genes (cat, mn-sod, gpx1a) and upregulation of innate immune-related genes (tlr4a, myd88, tnfα, il1β) as well as increased proinflammation cytokine contents (TNF-α, IL-1β, IL-6) were noticed in F1 offspring without/with continued MC-LR exposures. In addition, significant differences between the two F1 embryo treatments demonstrated that continuous MC-LR exposure could result in a higher degree of inflammatory response compared to those without MC-LR exposure. Our findings revealed that MC-LR could exert cross-generational effects of immunotoxicity by inhibiting the antioxidant system and activating an inflammatory response.