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The morphological development of rice (Oryza sativa L.) leaves is closely related to plant architecture, physiological activities, and resistance. However, it is unclear whether there is a co-regulatory relationship between the morphological development of leaves and adaptation to drought environment. In this study, a drought-sensitive, roll-enhanced, and narrow-leaf mutant (renl1) was induced from a semi-rolled leaf mutant (srl1) by ethyl methane sulfonate (EMS), which was obtained from Nipponbare (NPB) through EMS. Map-based cloning and functional validation showed that RENL1 encodes a cellulose synthase, allelic to NRL1/OsCLSD4. The RENL1 mutation resulted in reduced vascular bundles, vesicular cells, cellulose, and hemicellulose contents in cell walls, diminishing the water-holding capacity of leaves. In addition, the root system of the renl1 mutant was poorly developed and its ability to scavenge reactive oxygen species (ROS) was decreased, leading to an increase in ROS after drought stress. Meanwhile, genetic results showed that RENL1 and SRL1 synergistically regulated cell wall components. Our results revealed a theoretical basis for further elucidating the molecular regulation mechanism of cellulose on rice drought tolerance, and provided a new genetic resource for enhancing the synergistic regulation network of plant type and stress resistance, thereby realizing simultaneous improvement of multiple traits in rice.

Objectives: Traditional Chinese medicine (TCM) injections are extensively utilized for the treatment of transient ischemic attack (TIA). However, it remains unclear which specific TCM injection exhibits superior efficacy. In this study, we conducted a network meta-analysis to compare the clinical efficacy and safety of various TCM injections in the treatment of TIA, with the aim of identifying the optimal treatment regimen. Design: We searched seven databases to collect information on nine TCM injections for the treatment of transient randomized controlled trials (RCTs) for the treatment of transient ischemic attacks were collected from the establishment to August 2023. The methodological quality and risk of bias were assessed using the RoB 2.0 evaluation tool, and reticulated Meta-analysis was performed using R software and Stata software. Results: We ultimately included 58 RCTs involving 5502 patients and comprising 9 TCM injections. In terms of improving the total effective rate, Shuxuetong injection (P-score = 0.69) was the most effective. In addition, Shuxuetong injection was most effective in lowering total cholesterol (P-score = 1.00) and triglyceride (P-score = 1.00) levels. Notably, Shuxuetong injection remained the most prominent in reducing fibrinogen (P-score = 0.91). However, among other blood hemorheology indicators, Dengzhanhuasu injection was the best regimen in reducing plasma viscosity (P-score = 1.00), whole blood viscosity (high shear rate) (P-score = 0.87), and whole blood viscosity (low shear rate) (P-score = 0.90). It was found that Yinxingyetiquwu injection (P-score = 0.72) was the most effective in reducing the incidence of cerebral infarction. In terms of safety, 22 studies reported adverse effects and descriptive analyses showed that the number of adverse effects of combination therapy was comparable to that of conventional therapy and that the safety profile was good. Conclusions: TCM injections in combination with CT may be a safe and effective intervention for patients with TIA, of which Shuxuetong injection, Dengzhanhuasu injection, and Yinxingyetiquwu injection may be more noteworthy. The quality of the literature included in the study was low, so further validation is needed with larger sample sizes, higher quality, and more rigorously designed RCTs. Systematic review registration: [PROSPERO], identifier [CRD42023443652]. [ABSTRACT FROM AUTHOR]

Summary: Grain weight is an important determinant of grain yield. However, the underlying regulatory mechanisms for grain size remain to be fully elucidated. Here, we identify a rice mutant grain weight 9 (gw9), which exhibits larger and heavier grains due to excessive cell proliferation and expansion in spikelet hull. GW9 encodes a nucleus‐localized protein containing both C2H2 zinc finger (C2H2‐ZnF) and VRN2‐EMF2‐FIS2‐SUZ12 (VEFS) domains, serving as a negative regulator of grain size and weight. Interestingly, the non‐frameshift mutations in C2H2‐ZnF domain result in increased plant height and larger grain size, whereas frameshift mutations in both C2H2‐ZnF and VEFS domains lead to dwarf and malformed spikelet. These observations indicated the dual functions of GW9 in regulating grain size and floral organ identity through the C2H2‐ZnF and VEFS domains, respectively. Further investigation revealed the interaction between GW9 and the E3 ubiquitin ligase protein GW2, with GW9 being the target of ubiquitination by GW2. Genetic analyses suggest that GW9 and GW2 function in a coordinated pathway controlling grain size and weight. Our findings provide a novel insight into the functional role of GW9 in the regulation of grain size and weight, offering potential molecular strategies for improving rice yield. [ABSTRACT FROM AUTHOR]

An ideal leaf shape is beneficial to the yield of rice. Molecular understanding of the leaf primordia and polarity establishment plays a significant role in exploring the genetic regulatory network of leaf morphogenesis. In recent years, researchers have cloned an array of coding genes and a few non-coding small RNAs involved in rice leaf development through regulating the development of leaf primordia, vascular bundles, sclerenchyma cells, bulliform cells, cell walls and epidermis cells. These genes and their interactions play critical roles in rice leaf development through the determination and regulatory role in gene expression, and their coordination with other genetic networks or signal pathways. But the relationship among these genes is poorly defined and the underlying network is still unclear. In this review, we introduced the regulatory pathways of leaf primordium development and leaf polarity establishment, mainly the relationship between cell development mechanism and leaf polarity establishment, focusing on how leaf tissue affects leaf shape. Hopefully, the regulation network reviewed here has immediate implications for future research and genomic design breeding.

SUMMARY: Rice is an important food crop in China, and the development of hybrid rice is a crucial way to increase grain yield. The creation of dual-purpose nuclear-sterile lines for two-line hybrid breeding has become vital for commercial rice breeding. We constructed the pC1300-2x35S::Cas9-sgRNAPTGMS2-1 expression vector for editing the male fertility gene PTGMS2-1 in two widely compatible rice varieties, 93-11 and Huazhan, by using the CRISPR/Cas9 system. We obtained the marker-free photoperiod-/thermo- sensitive genic male-sterile (P/TGMS) lines in T1 generation. According to the experiments in phytotron with four temperature and photoperiod treatments, we found the temperature is the main factor for restoring the pollen fertility of ptgms2-1 mutants in 93-11 and Huazhan, and the photoperiod also has some effects on pollen fertility in two different rice backgrounds. The application of cultivating new male-sterile lines by genome editing system will significantly accelerate the rice breeding process.