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Starch biosynthesis involves numerous enzymes and is a crucial metabolic activity in plant storage organs. Sucrose non-fermenting related protein kinase 2 (SnRK2) is an abscisic acid (ABA)-dependent kinase and a significant regulatory enzyme in the ABA signaling pathway. However, whether SnRK2 kinases regulate starch biosynthesis is unclear. In this study, we identified that MeSnRK2.3 , encoding an ABA-dependent kinase, was highly expressed in the storage roots of cassava (Manihot esculenta) and was induced by ABA. Overexpression of MeSnRK2.3 in cassava significantly increased the starch content in the storage roots and promoted plant growth. MeSnRK2.3 was further found to interact with the cassava basic helix–loop–helix 68 (MebHLH68) transcription factor in vivo and in vitro. MebHLH68 directly bound to the promoters of sucrose synthase 1 (MeSUS1), granule-bound starch synthase I a (MeGBSSIa), and starch-branching enzyme 2.4 (MeSBE2.4), thereby up-regulating their transcriptional activities. Additionally, MebHLH68 negatively regulated the transcriptional activity of sucrose phosphate synthase B (MeSPSB). Moreover, MebHLH68 phosphorylated by MeSnRK2.3 up-regulated the transcription activity of MeSBE2.4. These findings demonstrated that the MeSnRK2.3–MebHLH68 module connects the ABA signaling pathway and starch biosynthesis in cassava, thereby providing direct evidence of ABA-mediated participation in the sucrose metabolism and starch biosynthesis pathways. [ABSTRACT FROM AUTHOR]

Cassava starch is a widely used raw material for industrial production and food source for people. However, cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis (Xam) results in severe yield losses and is the most destructive bacterial disease in all worldwide cassava‐growing regions. Xam11 is a highly pathogenic subspecies from China that infects the Chinese local cassava South China No. 8 (SC8) cultivar with marked symptoms. This study showed that the transcription activator‐like effector TALE20Xam11 of Xam11 strain regulates the expression of disease‐susceptibility gene MeSWEET10a by binding to the EBETALE20 region of the MeSWEET10a promoter in cassava cultivar SC8. CRISPR/Cas9‐generated mutations of the EBETALE20 region resulted in a significant reduction in MeSWEET10a expression after infection by Xam11, correlating with reduced disease symptoms, smaller lesion sizes and decreased bacterial proliferation compared with the wild type. Importantly, the edited plants maintained normal growth, development and yield characteristics under greenhouse conditions. The results lay a research foundation for breeding resistant cassava cultivar SC8 to bacterial blight. [ABSTRACT FROM AUTHOR]

Dirigent (DIR) genes play a pivotal role in plant development and stress adaptation. Manihot esculenta Crantz, commonly known as cassava, is a drought-resistant plant thriving in tropical and subtropical areas. It is extensively utilized for starch production, bioethanol, and animal feed. However, a comprehensive analysis of the DIR family genes remains unexplored in cassava, a crucial cash and forage crop in tropical and subtropical regions. In this study, we characterize a total of 26 cassava DIRs (MeDIRs) within the cassava genome, revealing their uneven distribution across 13 of the 18 chromosomes. Phylogenetic analysis classified these genes into four subfamilies: DIR-a, DIR-b/d, DIR-c, and DIR-e. Comparative synteny analysis with cassava and seven other plant species (Arabidopsis (Arabidopsis thaliana), poplar (Populus trichocarpa), soybean (Glycine max), tomato (Solanum lycopersicum), rice (Oryza sativa), maize (Zea mays), and wheat (Triticum aestivum)) provided insights into their likely evolution. We also predict protein interaction networks and identify cis-acting elements, elucidating the functional differences in MeDIR genes. Notably, MeDIR genes exhibited specific expression patterns across different tissues and in response to various abiotic and biotic stressors, such as pathogenic bacteria, cadmium chloride (CdCl2), and atrazine. Further validation through quantitative real-time PCR (qRT-PCR) confirmed the response of DIR genes to osmotic and salt stress. These findings offer a comprehensive resource for understanding the characteristics and biological functions of MeDIR genes in cassava, enhancing our knowledge of plant stress adaptation mechanisms. [ABSTRACT FROM AUTHOR]

Drought presents a significant abiotic stress that threatens crop productivity worldwide. Rhizosphere bacteria play pivotal roles in modulating plant growth and resilience to environmental stresses. Despite this, the extent to which rhizosphere bacteria are instrumental in plant responses to drought, and whether distinct cassava (Manihot esculenta Crantz) varieties harbor specific rhizosphere bacterial assemblages, remains unclear. In this study, we measured the growth and physiological characteristics, as well as the physical and chemical properties of the rhizosphere soil of drought-tolerant (SC124) and drought-sensitive (SC8) cassava varieties under conditions of both well-watered and drought stress. Employing 16S rDNA high-throughput sequencing, we analyzed the composition and dynamics of the rhizosphere bacterial community. Under drought stress, biomass, plant height, stem diameter, quantum efficiency of photosystem II (Fv/Fm), and soluble sugar of cassava decreased for both SC8 and SC124. The two varieties' rhizosphere bacterial communities' overall taxonomic structure was highly similar, but there were slight differences in relative abundance. SC124 mainly relied on Gamma-proteobacteria and Acidobacteriae in response to drought stress, and the abundance of this class was positively correlated with soil acid phosphatase. SC8 mainly relied on Actinobacteria in response to drought stress, and the abundance of this class was positively correlated with soil urease and soil saccharase. Overall, this study confirmed the key role of drought-induced rhizosphere bacteria in improving the adaptation of cassava to drought stress and clarified that this process is significantly related to variety. [ABSTRACT FROM AUTHOR]

Glyphosate, widely used to manage weeds in cassava crops, simultaneously inhibits cassava growth, necessitating the development of herbicide-tolerant cassava varieties. In this study, screened 262 cassava varieties, identifying the glyphosate-resistant (GR) variety ZM8701 and the glyphosate-sensitive (GS) variety SC9. Transcriptomic analysis via Illumina sequencing revealed differentially expressed genes associated with resistance, including Cytochrome P450, GST, GT, ABC transporters, and others such as MIOX1, LHCA1, PPH, HSP26, HSP83A, and UGT73C5. Notably, the EMB3004 gene, involved in the biosynthesis of aromatic amino acids, was significantly upregulated in resistant varieties, suggesting a key role in countering glyphosate's inhibition of the shikimic acid pathway. These genes are pivotal in enhancing cell wall biosynthesis, optimizing photosynthesis, and improving detoxification processes. This research elucidated the molecular mechanisms underlying cassava's resistance to glyphosate, thereby laying the groundwork for breeding programs aimed at developing herbicide-resistant varieties. [ABSTRACT FROM AUTHOR]

Gliomas, the most lethal tumours in brain, have a poor prognosis despite accepting standard treatment. Limited benefits from current therapies can be attributed to genetic, epigenetic and microenvironmental cues that affect cell programming and drive tumour heterogeneity. Through the analysis of Hi‐C data, we identified a potassium‐chloride co‐transporter SLC12A5 associated with disrupted topologically associating domain which was downregulated in tumour tissues. Multiple independent glioma cohorts were included to analyse the characterization of SLC12A5 and found it was significantly associated with pathological features, prognostic value, genomic alterations, transcriptional landscape and drug response. We constructed two SLC12A5 overexpression cell lines to verify the function of SLC12A5 that suppressed tumour cell proliferation and migration in vitro. In addition, SLC12A5 was also positively associated with GABAA receptor activity and negatively associated with pro‐tumour immune signatures and immunotherapy response. Collectively, our study provides a comprehensive characterization of SLC12A5 in glioma and supports SLC12A5 as a potential suppressor of disease progression. [ABSTRACT FROM AUTHOR]

In this paper, we consider the $ k $-prize-collecting minimum power cover problem ($ k $-PCPC), which is defined as follows. Given a set $ X = \{x_1, x_2, $ $ \cdots, x_n\} $ of $ n $ points and a set $ S = \{s_1, s_2, \cdots, s_m\} $ of $ m $ sensors on the plane $ \mathbb{R}^2 $, an integer $ k $ satisfying $ 0 \leq k \leq n $ and a penalty function $ \pi: X \rightarrow \mathbb{R}_0^{+} $, each sensor $ s\in S $ can adjust its power $ p(s) $ and the covering range, which is a disk of radius $ r(s) $ satisfying $ p(s) = c\cdot r(s)^\alpha $, where $ \alpha\geq 1 $ and $ c>0 $ are constants. We are asked to determine a set of disks $ \mathcal{F} $ such that at least $ k $ points are covered, where the center of any disk in $ \mathcal{F} $ is a sensor. The objective is to minimize the total power of the set of disks $ \mathcal{F} $ plus the penalty of $ R $, where $ R $ is the set of points that are not covered by $ \mathcal{F} $. It has been proven that this problem is NP-hard and admits a $ 3^\alpha $-approximation algorithm. By using some properties of relaxed independent sets and combining the guessing technique and the primal-dual method, we design an $ O(\alpha) $-approximation algorithm. Numerical experiments are tested to evaluate the performance of the $ 3^\alpha $-approximation algorithm and our new algorithm. [ABSTRACT FROM AUTHOR]