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The seeds are invariably exposed to high-temperature conditions since global warming frequently causes abnormally high temperature. In order to investigate the physiological basis of high-temperature tolerance in seeds, we used intermediate Citrus maxima ‘Mansailong’ seeds as the research material, heated the seeds at different developmental stages, and simultaneously detected changes in seed morphology, contents of soluble protein and heat-stable protein, and cellular ultrastructure. The results were as follows: (1) The seed moisture content dramatically dropped between 23 and 49 weeks after flowering (WAF), whereas the percentage of DW/FW and fresh weight increased significantly. All of these indicators began to change quickly from 31 WAF and stabilized around 41 WAF. (2) At 29 WAF, the seeds acquired full seedling formation ability and a preliminary tolerance to high temperature; from there, the high-temperature tolerance gradually grew and improved quickly between 37 and 49 WAF. The improvement in high-temperature tolerance was accompanied by a steady increase in contents of soluble protein and heat-stable protein of seeds, from 23 to 49 WAF. The results of the correlation analysis showed a substantial positive correlation between the accumulation of heat-stable protein and soluble protein and the ability of seeds to tolerate high temperature. (3) Ultrastructural observation showed that the number of mitochondria progressively dropped as the seed developed, the volume of the embryonic axis cells gradually decreased, and the number of lipid bodies in the cells gradually rose and their arrangement became more and more regular. In addition, the vacuoles enlarge at the same time, and at a later stage, they were packed with black floccules. In conclusion, the C. maxima ‘Mansailong’ seeds reach physiological maturity at 41 WAF without any noticeable maturation drying; the ability to tolerate high temperature is acquired during seed development and is further enhanced until a later stage; changes in cellural ultrastructure and an increase in contents of soluble protein and heat-stable protein of seeds are essential in helping the seeds develop their high-temperature tolerance.

NOAA Daily Optimum Interpolation Sea Surface Temperature (DOISST) and other similar sea surface temperature (SST) products indicate that the globally averaged SST set a new daily record in March 2023. The record‐high SST in March was immediately broken in April, and new daily records were set again in July and August 2023. The SST anomaly (SSTA) persisted at a record high from mid‐March to the remainder of 2023. Our analysis indicates that the record‐high SSTs, and associated marine heatwaves (MHWs) and even super‐MHWs, are attributed to three factors: (a) a long‐term warming trend, (b) a shift to the warm phase of the multi‐decadal Pacific‐Atlantic‐Arctic (PAA) mode, and (c) the transition from the triple‐dip succession of La Niña events to the 2023–24 El Niño event. Plain Language Summary: Observation‐based analyses such as the NOAA DOISST show that global mean SST reached a record high in April 2023, breaking the previous record of global mean SST set in March 2016, and the April 2023 record of global mean SST was broken again in July and August 2023. Our study indicates that these record‐breaking SSTs in 2023 resulted from record‐high SSTs over much of the global oceans and associated with widespread marine heatwaves (MHWs). Further analyses show that the record‐high SSTs are attributed to a long‐term‐warming trend associated with increasing greenhouse gases, a shift to the warm phase of a multidecadal Pacific‐Atlantic‐Arctic (PAA) mode, and a warming associated with the transition from 2020–23 La Niña events to the 2023–24 El Niño event. Key Points: Global mean sea surface temperature (SST) in 2023 set a record highRecord‐high SST was associated with widespread marine heatwaves (MHWs) and super‐MHWs throughout the oceansRecord‐high SST was attributed to the multi‐decadal warming trend, warm phase of Pacific‐Atlantic‐Arctic mode, and 2023–24 El Niño event [ABSTRACT FROM AUTHOR]

The heading date of rice is a crucial agronomic characteristic that influences its adaptability to different regions and its productivity potential. Despite the involvement of WRKY transcription factors in various biological processes related to development, the precise mechanisms through which these transcription factors regulate the heading date in rice have not been well elucidated. The present study identified OsWRKY11 as a WRKY transcription factor which exhibits a pivotal function in the regulation of the heading date in rice through a comprehensive screening of a clustered regularly interspaced palindromic repeats (CRISPR) ‒ CRISPR‐associated nuclease 9 mutant library that specifically targets the WRKY genes in rice. The heading date of oswrky11 mutant plants and OsWRKY11‐overexpressing plants was delayed compared with that of the wild‐type plants under short‐day and long‐day conditions. Mechanistic investigation revealed that OsWRKY11 exerts dual effects on transcriptional promotion and suppression through direct and indirect DNA binding, respectively. Under normal conditions, OsWRKY11 facilitates flowering by directly inducing the expression of OsMADS14 and OsMADS15. The presence of elevated levels of OsWRKY11 protein promote formation of a ternary protein complex involving OsWRKY11, Heading date 1 (Hd1), and Days to heading date 8 (DTH8), and this complex then suppresses the expression of Ehd1, which leads to a delay in the heading date. Subsequent investigation revealed that a mild drought condition resulted in a modest increase in OsWRKY11 expression, promoting heading. Conversely, under severe drought conditions, a significant upregulation of OsWRKY11 led to the suppression of Ehd1 expression, ultimately causing a delay in heading date. Our findings uncover a previously unacknowledged mechanism through which the transcription factor OsWRKY11 exerts a dual impact on the heading date by directly and indirectly binding to the promoters of target genes. [ABSTRACT FROM AUTHOR]

Due to their atomically dispersed active centers, single‐atom nanozymes (SAzymes) have unparalleled advantages in cancer catalytic therapy. Here, loaded with chlorin e6 (Ce6), a hydrothermally mass‐produced bimetallic silicate‐based nanoplatforms with atomically dispersed manganese/gadolinium (Mn/Gd) dual sites and oxygen vacancies (OVs) (PMnSAGMSNs‐V@Ce6) is constructed for tumor glutathione (GSH)‐triggered chemodynamic therapy (CDT) and O2‐alleviated photodynamic therapy. The band gaps of silica are significantly reduced from 2.78 to 1.88 eV by doping with metal ions, which enables it to be excited by a 650 nm laser to produce electron‐hole pairs, thereby facilitating the generation of reactive oxygen species. The Gd sites can modulate the local electrons of the atom‐catalyzed Mn sites, which contribute to the generation of superoxide and hydroxyl radicals (•OH). Tumor GSH‐triggered Mn2+ release can convert endogenous H2O2 to •OH and realize GSH‐depletion‐enhanced CDT. Significantly, the hydrothermally generated OVs can not only capture Mn and Gd atoms to form atomic sites but also can elongate and weaken the O‐O bonds of H2O2, thereby improving the efficacy of Fenton reactions. The degraded Mn2+/Gd3+ ions can be used as tumor‐specific magnetic resonance imaging contrast agents. All the experimental results demonstrate the great potential of PMnSAGMSNs‐V@Ce6 as cancer theranostic agent. [ABSTRACT FROM AUTHOR]