FLOURY ENDOSPERM24, a heat shock protein 101 (HSP101), is required for starch biosynthesis and endosperm development in rice.

Endosperm is the main storage organ in cereal grain and determines grain yield and quality. The molecular mechanisms of heat shock proteins in regulating starch biosynthesis and endosperm development remain obscure. Here, we report a rice floury endosperm mutant flo24 that develops abnormal starch grains in the central starchy endosperm cells. Map-based cloning and complementation test showed that FLO24 encodes a heat shock protein HSP101, which is localized in plastids. The mutated protein FLO24T296I dramatically lost its ability to hydrolyze ATP and to rescue the thermotolerance defects of the yeast hsp104 mutant. The flo24 mutant develops more severe floury endosperm when grown under high-temperature conditions than normal conditions. And the FLO24 protein was dramatically induced at high temperature. FLO24 physically interacts with several key enzymes required for starch biosynthesis, including AGPL1, AGPL3 and PHO1. Combined biochemical and genetic evidence suggests that FLO24 acts cooperatively with HSP70cp-2 to regulate starch biosynthesis and endosperm development in rice. Our results reveal that FLO24 acts as an important regulator of endosperm development, which might function in maintaining the activities of enzymes involved in starch biosynthesis in rice.

Electrospun Sandwich-like Structure of PVDF-HFP/Cellulose/PVDF-HFP Membrane for Lithium-Ion Batteries.

Cellulose membranes have eco-friendly, renewable, and cost-effective features, but they lack satisfactory cycle stability as a sustainable separator for batteries. In this study, a two-step method was employed to prepare a sandwich-like composite membrane of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)/cellulose/ PVDF-HFP (PCP). The method involved first dissolving and regenerating a cellulose membrane and then electrospinning PVDF-HFP on its surface. The resulting PCP composite membrane exhibits excellent properties such as high porosity (60.71%), good tensile strength (4.8 MPa), and thermal stability up to 160 °C. It also has exceptional electrolyte uptake properties (710.81 wt.%), low interfacial resistance (241.39 Ω), and high ionic conductivity (0.73 mS/cm) compared to commercial polypropylene (PP) separators (1121.4 Ω and 0.26 mS/cm). Additionally, the rate capability (163.2 mAh/g) and cycling performance (98.11% after 100 cycles at 0.5 C) of the PCP composite membrane are superior to those of PP separators. These results demonstrate that the PCP composite membrane has potential as a promising separator for high-powered, secure lithium-ion batteries.

A deleterious Sar1c variant in rice inhibits export of seed storage proteins from the endoplasmic reticulum.

KEY MESSAGE: We identified a dosage-dependent dominant negative form of Sar1c, which confirms the essential role of COPII system in mediating ER export of storage proteins in rice endosperm. Higher plants accumlate large amounts of seed storage proteins (SSPs). However, mechanisms underlying SSP trafficking are largely unknown, especially the ER-Golgi anterograde process. Here, we showed that a rice glutelin precursor accumulation13 (gpa13) mutant exhibited floury endosperm and overaccumulated glutelin precursors, which phenocopied the reported RNAi-Sar1abc line. Molecular cloning revealed that the gpa13 allele encodes a mutated Sar1c (mSar1c) with a deletion of two conserved amino acids Pro134 and Try135. Knockdown or knockout of Sar1c alone caused no obvious phenotype, while overexpression of mSar1c resulted in seedling lethality similar to the gpa13 mutant. Transient expression experiment in tobacco combined with subcellular fractionation experiment in gpa13 demonstrated that the expression of mSar1c affects the subcellular distribution of all Sar1 isoforms and Sec23c. In addition, mSar1c failed to interact with COPII component Sec23. Conversely, mSar1c competed with Sar1a/b/d to interact with guanine nucleotide exchange factor Sec12. Together, we identified a dosage-dependent dominant negative form of Sar1c, which confirms the essential role of COPII system in mediating ER export of storage proteins in rice endosperm.

[Reconstruction of external nose defect with local flaps].

OBJECTIVE: The role of different local flaps in small external nasal skin defect reconstruction was discussed. METHOD: Forty-two cases of the small size nasal defects (diameter < 2 cm) were repaired with local external nose flap (includes the dorsal nasal flap, nasolabial flap and bilobed flap). The clinical and follow-up data were analyzed of patients with small external nasal skin defects, who accepted different local flaps reconstruction. Dorsal nasal flap, nasolabial flaps (includes island flap, slid flap and axial flap) and bilobed flap were tailored to reconstruct different external nasal defect. Twenty-seven patients were male and fifteen patients were female, the patients' age ranged from 28 to 74 years, the median age was 61 years. Thirty-eight cases resulted from resection of skin malignant tumor and four cases were benign lesions. The diameter of defects was 1-2 cm. The defects were reconstructed by single-stage dorsal nasal flap in 7 cases. There were 30 cases of caudolateral nasal defects were reconstructed by nasolabial flap, single-stage island nasolabial flap in 7 cases, axial flap in 18 cases and slid flap in 5 cases. Superior lateral defects were reconstructed by single-stage bilobed flap in 5 cases. RESULT: All defects were repaired successfully. All tissue flaps survived and had not necrosis. There was no tumor recurrence during 3 months to 2 years follow-up. CONCLUSION: The dorsal nasal flap, nasolabial flap and bilobed flap can be used safely and effectively to repair the small external nasal defect and have satisfactory curative effect.