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Key message: A novel light-dependent dominant lesion mimic mutant with enhanced multiple disease resistance was physiologically, biochemically, and genetically characterized; the causal gene was fine mapped to a 909 kb interval containing 38 genes. Identification of genes that confer multiple disease resistance (MDR) is crucial for the improvement of maize disease resistance. However, very limited genes are identified as MDR genes in maize. In this study, we characterized a dominant disease lesion mimics 8 (Les8) mutant that had chlorotic lesions on the leaves and showed enhanced resistance to both curvularia leaf spot and southern leaf blight. Major agronomic traits were not obviously altered, while decreased chlorophyll content was observed in the mutant, and the genetic effect of the Les8 mutation was stable in different genetic backgrounds. By BSR-seq analysis and map-based cloning, the LES8 gene was mapped into a 909 kb region containing 38 candidate genes on chromosome 9 wherein no lesion mimic or disease-resistance genes were previously reported. Using transcriptomics analysis, we found that genes involved in defense responses and secondary metabolite biosynthesis were enriched in the significantly up-regulated genes, while genes involved in photosynthesis and carbohydrate-related pathways were enriched in the significantly down-regulated genes in Les8. In addition, there was an overaccumulation of jasmonic acid and lignin but not salicylic acid in Les8. Taken together, this study revealed candidate genes and potential mechanism underlying Les8-conferred MDR in maize. [ABSTRACT FROM AUTHOR]

The cultural deposits at pits T1 and T2 in Zhangkou Cave are intercalated with several flowstone layers. U-series dates show that the capping and 2nd flowstone layers are Holocene of age. The 4th and 5th flowstone layers are ca. 55 and 110 ka old respectively. The lithic artifacts bracketed by them provide unequivocal evidence for hominid presence during this time interval. The ┐temporal gap” of hominid fossil, widely quoted as in support of the out-of-Africa hypothesis, is most probably an artifact due to systematic errors of dating techniques. The infillings under 6th flowstone layer date to > 300 ka, much older than the previous estimate at 15 ka based on classical14C dating of fossil bones, providing one more example of the limited reliability of this chronometer. With rich relics and favorable conditions for precise dating, this site is promising for further multidisciplinary studies to address issues concerning recent human evolution in China. [ABSTRACT FROM AUTHOR]

The cultural deposits at pits Ti and T2 in Zhangkou Cave are intercalated with several flowstone layers. U-series dates show that the capping and 2nd flowstone layers are Holocene of age. The 4th and 5th flowstone layers are ca. 55 and 110 ka old respectively. The lithic artifacts bracketed by them provide unequivocal evidence for hominid presence during this time interval. The "temporal gap" of hominid fossil, widely quoted as in support of the out-of-Africa hypothesis, is most probably an artifact due to systematic errors of dating techniques. The infillings under 6th flowstone layer date to >300 ka, much older than the previous estimate at 15 ka based on classical 14C dating of fossil bones, providing one more example of the limited reli- ability of this chronometer. With rich relics and favorable conditions for precise dating, this site is promising for further multidisciplinary studies to address issues concerning recent human evolution in China. [ABSTRACT FROM AUTHOR]

MYC has been identified to profoundly influence a wide range of pathologic processes in cancers. However, the prognostic value of MYC-related genes in pancreatic adenocarcinoma (PAAD) remains unclarified. Gene expression data and clinical information of PAAD patients were obtained from The Cancer Genome Atlas (TCGA) database (training set). Validation sets included GSE57495, GSE62452, and ICGC-PACA databases. LASSO regression analysis was used to develop a risk signature for survival prediction. Single-cell sequencing data from GSE154778 and CRA001160 datasets were analyzed. Functional studies were conducted using siRNA targeting RHOF and ITGB6 in PANC-1 cells. High MYC expression was found to be significantly associated with a poor prognosis in patients with PAAD. Additionally, we identified seven genes (ADGRG6, LINC00941, RHOF, SERPINB5, INSYN2B, ITGB6, and DEPDC1) that exhibited a strong correlation with both MYC expression and patient survival. They were then utilized to establish a risk model (MYCsig), which showed robust predictive ability. Furthermore, MYCsig demonstrated a positive correlation with the expression of HLA genes and immune checkpoints, as well as the chemotherapy response of PAAD. RHOF and ITGB6, expressed mainly in malignant cells, were identified as key oncogenes regulating chemosensitivity through EMT. Downregulation of RHOF and ITGB6 reduced cell proliferation and invasion in PANC-1 cells. The developed MYCsig demonstrates its potential in enhancing the management of patients with PAAD by facilitating risk assessment and predicting response to adjuvant chemotherapy. Additionally, our study identifies RHOF and ITGB6 as novel oncogenes linked to EMT and chemoresistance in PAAD. [ABSTRACT FROM AUTHOR]