Identification and functional analysis of the DOF gene family in Populus simonii: implications for development and stress response.

Background: Populus simonii, a notable native tree species in northern China, demonstrates impressive resistance to stress, broad adaptability, and exceptional hybridization potential. DOF family is a class of specific transcription factors that only exist in plants, widely participating in plant growth and development, and also playing an important role in abiotic stress response. To date, there have been no reported studies on the DOF gene family in P. simonii, and the expression levels of this gene family in different tissues of poplar, as well as its expression patterns under cold, heat, and other stress conditions, remain unclear. Methods: In this study, DOF gene family were identified from the P. simonii genome, and various bioinformatics data on the DOF gene family, gene structure, gene distribution, promoters and regulatory networks were analyzed. Quantitative real time PCR technology was used to verify the expression patterns of the DOF gene family in different poplar tissues. Results: This research initially pinpointed 41 PSDOF genes in P. simonii genome. The chromosomal localization results revealed that the PSDOF genes is unevenly distributed among 19 chromosomes, with the highest number of genes located on chromosomes 4, 5, and 11. A phylogenetic tree was constructed based on the homology between Arabidopsis thaliana and P. simonii, dividing the 41 PSDOF genes into seven subgroups. The expression patterns of PSDOF genes indicated that specific genes are consistently upregulated in various tissues and under different stress conditions, suggesting their pivotal involvement in both plant development and response to stress. Notably, PSDOF35 and PSDOF28 serve as pivotal hubs in the interaction network, playing a unique role in coordinating with other genes within the family. Conclusion: The analysis enhances our comprehension of the functions of the DOF gene family in tissue development and stress responses within P. simonii. These findings provide a foundation for future exploration into the biological roles of DOF gene family.

Unraveling the Guardians of Growth: A Comprehensive Analysis of the Aux/IAA and ARF Gene Families in Populus simonii.

The auxin/indole-3-acetic acid (Aux/IAA) and auxin response factor (ARF) genes are two crucial gene families in the plant auxin signaling pathway. Nonetheless, there is limited knowledge regarding the Aux/IAA and ARF gene families in Populus simonii. In this study, we first identified 33 putative PsIAAs and 35 PsARFs in the Populus simonii genome. Analysis of chromosomal location showed that the PsIAAs and PsARFs were distributed unevenly across 17 chromosomes, with the greatest abundance observed on chromosomes 2. Furthermore, based on the homology of PsIAAs and PsARFs, two phylogenetic trees were constructed, classifying 33 PsIAAs and 35 PsARFs into three subgroups each. Five pairs of PsIAA genes were identified as the outcome of tandem duplication, but no tandem repeat gene pairs were found in the PsARF family. The expression profiling of PsIAAs and PsARFs revealed that several genes exhibited upregulation in different tissues and under various stress conditions, indicating their potential key roles in plant development and stress responses. The variance in expression patterns of specific PsIAAs and PsARFs was corroborated through RT-qPCR analysis. Most importantly, we instituted that the PsIAA7 gene, functioning as a central hub, exhibits interactions with numerous Aux/IAA and ARF proteins. Furthermore, subcellular localization findings indicate that PsIAA7 functions as a protein localized within the nucleus. To conclude, the in-depth analysis provided in this study will contribute significantly to advancing our knowledge of the roles played by PsIAA and PsARF families in both the development of P. simonii tissue and its responses to stress. The insights gained will serve as a valuable asset for further inquiries into the biological functions of these gene families.

Variation of Chromosome Composition in a Full-Sib Population Derived From 2x × 3x Interploidy Cross of Populus.

Interploidy cross commonly results in complex chromosome number and structural variations. In our previous study, a progeny with segregated ploidy levels was produced by an interploidy cross between diploid female parent Populus tomentosa × Populus bolleana clone TB03 and triploid male parent Populus alba × Populus berolinensis 'Yinzhong'. However, the chromosome compositions of aneuploid genotypes in the progeny were still unclear. In the present study, a microsatellite DNA allele counting-peak ratios (MAC-PR) method was employed to analyze allelic configurations of each genotype to clarify their chromosome compositions, while 45S rDNA fluorescence in situ hybridization (FISH) analysis was used to reveal the mechanism of chromosome number variation. Based on the MAC-PR analysis of 47 polymorphic simple sequence repeat (SSR) markers distributed across all 19 chromosomes of Populus, both chromosomal number and structural variations were detected for the progeny. In the progeny, 26 hypo-triploids, 1 hyper-triploid, 16 hypo-tetraploids, 10 tetraploids, and 5 hyper-tetraploids were found. A total of 13 putative structural variation events (duplications and/or deletions) were detected in 12 genotypes, involved in chromosomes 3, 6, 7, 14, 15, 16, and 18. The 46.2% (six events) structural variation events occurred on chromosome 6, suggesting that there probably is a chromosome breakpoint near the SSR loci of chromosome 6. Based on calculation of the allelic information, the transmission of paternal heterozygosity in the hypo-triploids, hyper-triploid, hypo-tetraploids, tetraploids, and hyper-tetraploids were 0.748, 0.887, 0.830, 0.833, and 0.836, respectively, indicating that the viable pollen gains of the male parent 'Yinzhong' were able to transmit high heterozygosity to progeny. Furthermore, 45S rDNA-FISH analysis showed that specific-chromosome segregation feature during meiosis and chromosome appointment in normal and fused daughter nuclei of telophase II of 'Yinzhong,' which explained that the formation of aneuploids and tetraploids in the progeny could be attributed to imbalanced meiotic chromosomal segregation and division restitution of 'Yinzhong,' The data of chromosomal composition and structural variation of each aneuploid in the full-sib progeny of TB03 × 'Yinzhong' lays a foundation for analyzing mechanisms of trait variation relying on chromosome or gene dosages in Populus.

Synthesis of oxindoles through trifluoromethylation of N-aryl acrylamides by photoredox catalysis.

Mild and direct intramolecular oxidative aryltrifluoromethylations of activated alkenes have been established through visible light photocatalysis, affording a range of CF3-containing oxindoles or isoquinolinediones in the presence of an organic fluorophore-type photocatalyst 4CzIPN, oxygen and visible light irradiation under strong oxidant and transition metal free conditions. A variety of frequently encountered functional groups are well tolerated in this transformation.