The exploration of mitochondrial-related features helps to reveal the prognosis and immunotherapy methods of colorectal cancer.

BACKGROUND: Cancer cell survival, proliferation, and metabolism are all intertwined with mitochondria. However, a complete description of how the features of mitochondria relate to the tumor microenvironment (TME) and immunological landscape of colorectal cancer (CRC) has yet to be made. We performed subgroup analysis on CRC patient data obtained from the databases using non-negative matrix factorization (NMF) clustering. Construct a prognostic model using the mitochondrial-related gene (MRG) risk score, and then compare it to other models for accuracy. Comprehensive analyses of the risk score, in conjunction with the TME and immune landscape, were performed, and the relationship between the model and different types of cell death, radiation and chemotherapy, and drug resistance was investigated. Results from immunohistochemistry and single-cell sequencing were utilized to verify the model genes, and a drug sensitivity analysis was conducted to evaluate possible therapeutic medicines. The pan-cancer analysis is utilized to further investigate the role of genes in a wider range of malignancies. METHODS AND RESULTS: We found that CRC patients based on MRG were divided into two groups with significant differences in survival outcomes and TME between groups. The predictive power of the risk score was further shown by building a prognostic model and testing it extensively in both internal and external cohorts. Multiple immune therapeutic responses and the expression of immunological checkpoints demonstrate that the risk score is connected to immunotherapy success. The correlation analysis of the risk score provide more ideas and guidance for prognostic models in clinical treatment. CONCLUSION: The TME, immune cell infiltration, and responsiveness to immunotherapy in CRC were all thoroughly evaluated on the basis of MRG features. The comparative validation of multiple queues and models combined with clinical data ensures the effectiveness and clinical practicality of MRG features. Our studies help clinicians create individualized treatment programs for individuals with cancer.

LkARF7 and LkARF19 overexpression promote adventitious root formation in a heterologous poplar model by positively regulating LkBBM1.

Cuttage propagation involves adventitious root formation induced by auxin. In our previous study, Larix kaempferi BABY BOOM 1 (LkBBM1), which is known to regulate adventitious root formation, was affected by auxin. However, the relationship between LkBBM1 and auxin remains unclear. Auxin response factors (ARFs) are a class of important transcription factors in the auxin signaling pathway and modulate the expression of early auxin-responsive genes by binding to auxin response elements. In the present study, we identified 14 L. kaempferi ARFs (LkARFs), and found LkARF7 and LkARF19 bound to LkBBM1 promoter and enhanced its transcription using yeast one-hybrid, ChIP-qPCR, and dual-luciferase assays. In addition, the treatment with naphthalene acetic acid promoted the expression of LkARF7 and LkARF19. We also found that overexpression of these two genes in poplar promoted adventitious root formation. Furthermore, LkARF19 interacted with the DEAD-box ATP-dependent RNA helicase 53-like protein to form a heterodimer to regulate adventitious root formation. Altogether, our results reveal an additional regulatory mechanism underlying the control of adventitious root formation by auxin.

The Larix kaempferi genome reveals new insights into wood properties.

Here, through single-molecule real-time sequencing, we present a high-quality genome sequence of the Japanese larch (Larix kaempferi), a conifer species with great value for wood production and ecological afforestation. The assembled genome is 10.97 Gb in size, harboring 45,828 protein-coding genes. Of the genome, 66.8% consists of repeat sequences, of which long terminal repeat retrotransposons are dominant and make up 69.86%. We find that tandem duplications have been responsible for the expansion of genes involved in transcriptional regulation and stress responses, unveiling their crucial roles in adaptive evolution. Population transcriptome analysis reveals that lignin content in L. kaempferi is mainly determined by the process of monolignol polymerization. The expression values of six genes (LkCOMT7, LkCOMT8, LkLAC23, LkLAC102, LkPRX148, and LkPRX166) have significantly positive correlations with lignin content. These results indicated that the increased expression of these six genes might be responsible for the high lignin content of the larches' wood. Overall, this study provides new genome resources for investigating the evolution and biological function of conifer trees, and also offers new insights into wood properties of larches.

Development and characterization of polymorphic genic-SSR markers in Larix kaempferi.

New simple sequence repeat (SSR) markers were developed in the Japanese larch (Larix kaempferi) using unigene sequences for further genetic diversity studies and the genetic improvement of breeding programs. One thousand two handred and thirty five (1235) primer pairs were tested and 165 successfully identified in L. kaempferi. Out of the amplified candidate markers, 145 (90.6%) exhibited polymorphism among 24 individuals of L. kaempferi, with the number of alleles per locus (Na), observed heterozygosity (Ho), expected heterozygosity (He) and polymorphic information content (PIC) averaging at 4.510, 0.487, 0.518 and 0.459, respectively. Cross-species amplification of randomly selection of 30 genic-SSRs among the 145 polymorphic ones showed that 80.0% of the SSRs could be amplified in Larix olgensis, 86.7% could be amplified in Larix principi-rupprechtii and 83.0% could be amplified in Larix gmelinii. High rates of cross-species amplification were observed. The genic-SSRs developed herein would be a valuable resource for genetic analysis of Larix kaempferi and related species, and also have the potential to facilitate the genetic improvement and breeding of larch.