Integrated Metabolomic and Transcriptomic Analyses Reveals Sugar Transport and Starch Accumulation in Two Specific Germplasms of Manihot esculenta Crantz.

As a starchy and edible tropical plant, cassava (Manihot esculenta Crantz) has been widely used as an industrial raw material and a dietary source. However, the metabolomic and genetic differences in specific germplasms of cassava storage root were unclear. In this study, two specific germplasms, M. esculenta Crantz cv. sugar cassava GPMS0991L and M. esculenta Crantz cv. pink cassava BRA117315, were used as research materials. Results showed that sugar cassava GPMS0991L was rich in glucose and fructose, whereas pink cassava BRA117315 was rich in starch and sucrose. Metabolomic and transcriptomic analysis indicated that sucrose and starch metabolism had significantly changing metabolites enrichment and the highest degree of differential expression genes, respectively. Sugar transport in storage roots may contribute to the activities of sugar, which will eventually be exported to transporters (SWEETs), such as (MeSWEET1a, MeSWEET2b, MeSWEET4, MeSWEET5, MeSWEET10b, and MeSWEET17c), which transport hexose to plant cells. The expression level of genes involved in starch biosynthesis and metabolism were altered, which may result in starch accumulation. These results provide a theoretical basis for sugar transport and starch accumulation and may be useful in improving the quality of tuberous crops and increasing yield.

Integrative analysis of metabolome and transcriptome reveals the mechanism of color formation in cassava (Manihot esculenta Crantz) leaves.

Cassava (Manihot esculenta Crantz) leaves are often used as vegetables in Africa. Anthocyanins possess antioxidant, anti-inflammatory, anti-cancer, and other biological activities. They are poor in green leaves but rich in the purple leaves of cassava. The mechanism of anthocyanin's accumulation in cassava is poorly understood. In this study, two cassava varieties, SC9 with green leaves and Ziyehuangxin with purple leaves (PL), were selected to perform an integrative analysis using metabolomics and transcriptomics. The metabolomic analysis indicated that the most significantly differential metabolites (SDMs) belong to anthocyanins and are highly accumulated in PL. The transcriptomic analysis revealed that differentially expressed genes (DEGs) are enriched in secondary metabolites biosynthesis. The analysis of the combination of metabolomics and transcriptomics showed that metabolite changes are associated with the gene expressions in the anthocyanin biosynthesis pathway. In addition, some transcription factors (TFs) may be involved in anthocyanin biosynthesis. To further investigate the correlation between anthocyanin accumulation and color formation in cassava leaves, the virus-induced gene silencing (VIGS) system was used. VIGS-MeANR silenced plant showed the altered phenotypes of cassava leaves, partially from green to purple color, resulting in a significant increase of the total anthocyanin content and reduction in the expression of MeANR. These results provide a theoretical basis for breeding cassava varieties with anthocyanin-rich leaves.

Clinical efficacy of sertraline in the treatment of depression caused by Alzheimer disease: A protocol of systematic review.

BACKGROUND: This study will appraise the clinical efficacy of sertraline in the treatment of depression caused by Alzheimer disease (AD). METHODS: Comprehensive searches in PUBMED, EMBASE, Cochrane Library, Scopus, AMED, CNKI, and WANGFANG will be performed from inception to the present without language restriction. In addition, other sources will also be searched to avoid losing more potential studies. We will only consider randomized controlled trials that examined the efficacy of sertraline for depression in patients with AD. Two team members will independently undertake literature selection, data collection, and risk of bias assessment. We will use Cochrane Risk of Bias Tool to assess the risk of bias for each eligible trial, and will utilize RevMan 5.3 software to carry out data analysis. RESULTS: This study will recapitulate high-quality evidence to assess the efficacy of sertraline for the treatment of depression following AD. CONCLUSION: The findings of this study will help to determine whether or not sertraline is effective for the treatment of depression after AD. OSF REGISTRATION:: osf.io/f29v6.