Yujie Yang

The NAC (NAM/ATAF1/2/CUC2) transcription factors are pivotal regulators in plant development and stress responses. Despite the extensive studies on the NAC gene family across various plant species, the characterization of this gene family in mulberry (Morus atropurpurea) remains unexplored. Here, we conducted a genome-wide identification and characterization of the NAC gene family in M. atropurpurea. A total of 79 MaNAC genes were identified and classified into 20 subgroups, displaying an uneven distribution across the 14 chromosomes. The structural analysis found that most MaNAC genes possess at least three exons and contain the conserved NAC domain and characteristic motifs at the N-terminus. Eleven collinear gene pairs were identified in M. atropurpurea genome. Interspecies collinearity analysis demonstrated a closer evolutionary relationship between M. atropurpurea and Populus trichocarpa, supported by the identification of 116 collinear gene pairs. Expression profiling revealed dynamic changes in the transcript levels of most MaNAC genes during mulberry fruit maturation. Notably, the eight MaNAC members from the OsNAC7 subfamily exhibited tissue-specific expression patterns. A significant proportion of MaNAC genes displayed varying degrees of responsiveness to drought stress and sclerotium disease. MaNAC12, MaNAC32, MaNAC44 and MaNAC67 emerged as the most highly responsive candidates. Overexpression of MaNAC69 enhanced drought tolerance in Arabidopsis. These findings provide a robust foundation for future functional studies and mechanistic investigations into the roles of the NAC gene family in M. atropurpurea, offering insights into their contributions to development and stress adaptation.

Human activities lead to an increase in greenhouse gases in the environment, among which carbon dioxide (CO₂) is one of the most prominent, giving rise to global warming and climate change. Climate change, along with the resulting environmental degradation, is one of the most challenging difficulties faced by humanity in the twenty-first century. The forest ecosystem, with plants being its most important component, plays a pivotal role in regulating climate. Carbon sequestration and oxygen release (CSOR) by plants are major ecological service functions that play an important role in mitigating the negative impacts of the greenhouse effect and help to achieve carbon peaking and neutrality. The CSOR of mulberry (Morus spp.), a species of economic and ecological significance, is not yet understood. Six mulberry tree varieties were selected to evaluate their CSOR potential during summer. We took into consideration whole-plant diurnal assimilation amounts (P), carbon sequestration per unit leaf area (WCO₂), oxygen release per unit leaf area (WO₂), carbon sequestration per unit land area (PCO₂), and oxygen release per unit land area (PO₂). Zhongsang 1302 showed the greatest potential for CSOR among the six mulberry varieties. The PCO₂ value of the Zhongsang 1302 variety was 1531.84 g·m⁻² during summer, followed by Suhu 16 (1380.12 g·m⁻²), Husang 32 (1005.63 g·m⁻²), Zhongsang 9703 (990.01 g·m⁻²), Yu 711 (940.43 g·m⁻²), and Jin 10 (848.29 g·m⁻²). Moreover, the Pearson correlation and path analyses showed that photosynthetic rate (P_N) and leaf area index (LAI) mainly affect the overall CSOR potential in mulberry. These findings not only enrich theoretical research on CSOR in mulberry, but also serve as an important reference for the use of different mulberry tree varieties in improving climate conditions and achieving carbon peaking and neutrality.

Virus-induced gene silencing (VIGS) is an RNA-mediated reverse genetics technique that has become an effective tool to investigate gene function in plants. Cotton is one of the most important economic crops globally. In the past decade, VIGS has been successfully applied in cotton functional genomic studies, including those examining abiotic and biotic stress responses and vegetative and reproductive development. This article summarizes the traditional vectors used in the cotton VIGS system, the visible markers used for endogenous gene silencing, the applications of VIGS in cotton functional genomics, and the limitations of VIGS and how they can be addressed in cotton.

Cotton fibers provide an important source of raw materials for the textile industry worldwide. Cotton fiber is a kind of single cell that differentiates from the epidermis of the ovule and provides a perfect research model for the differentiation and elongation of plant cells. Cotton fiber initiation is the first stage throughout the entire developmental process. The number of fiber cell initials on the seed ovule epidermis decides the final fiber yield. Thus, it is of great significance to clarify the mechanism underlying cotton fiber initiation. Fiber cell initiation is controlled by complex and interrelated regulatory networks. Plant phytohormones, transcription factors, sugar signals, small signal molecules, functional genes, non-coding RNAs, and histone modification play important roles during this process. Here, we not only summarize the different kinds of factors involved in fiber cell initiation but also discuss the mechanisms of these factors that act together to regulate cotton fiber initiation. Our aim is to synthesize a systematic and comprehensive review of different factors during fiber initiation that will provide the basics for further illustrating these mechanisms and offer theoretical guidance for improving fiber yield in future molecular breeding work.