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The long-term cultivation of higher plants in space plays a substantial role in investigating the effects of microgravity on plant growth and development, acquiring valuable insights for developing a self-sustaining space life supporting system. The completion of the Chinese Space Station (CSS) provides us with a new permanent space experimental platform for long-term plant research in space. Biological Culture Module (GBCM), which was installed in the Wentian experimental Module of the CSS, was constructed with the objective of growing Arabidopsis thaliana and rice plants a full life cycle in space. The techniques of LED light control, gas regulation and water recovery have been developed for GBCM in which dry seeds of Arabidopsis and rice were set in root module of four culture chambers (CCs) and launched with Wentian module on July 24, 2022. These seeds were watered and germinated from July 28 and grew new seeds until November 26 within a duration of 120 days. To this end, both Arabidopsis and rice plants completed a full life cycle in microgravity on the CSS. As we know, this is the first space experiment achieving rice complete life cycle from seed-to-seed in space. This result demonstrates the possibility to cultivate the important food crop rice throughout its entire life cycle under the spaceflight environment and the technologies of GBCM have effectively supported the success of long-term plant culture experiments in space. These results can serve as invaluable references for constructing more expansive and intricate space plant cultivation systems in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

As significant phytoalexins, stilbene compounds can improve the stress resistance of grapes under biotic and abiotic stress conditions and have biological effects such as antitumour, antioxidant, immune regulation and cardiovascular protection activities in humans. RESVERATROL SYNTHASE (RS), also known as STILBENE SYNTHASE (STS), is the critical enzyme regulating stilbene synthesis and has been identified in a few plant species. However, the regulatory mechanisms of stilbene synthesis are uncertain. In this study, an NAC family transcription factor from Vitis quinquangularis, named VqNAC44, was characterized as an indirect regulator of stilbene synthesis. It is worth noting that VqNAC44 did not bind to the STS promoter nor did it interact with the STS protein but interacted with the MYB transcription factor VqMYB15. This interaction between VqMYB15 and VqNAC44 was validated by a yeast two-hybrid assay and bimolecular fluorescence complementation. Overexpressing VqNAC44 in Arabidopsis thaliana significantly increased its tolerance to biotic and abiotic stresses. Transient overexpression of VqNAC44 and VqMYB15 in grape leaves resulted in increased expression of the STS gene and increased production of stilbene compounds. The experimental results confirmed that VqNAC44 regulated stilbene synthesis by interacting with VqMYB15, thereby enhancing the plant stress resistance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Both cytokinin and NAC transcription factors were reported to involve in leaf senescence. However, the mechanism of NAC transcription factors how to regulate cytokinin-delayed leaf senescence is still unknown. In this study, application of N-(2-chloro-4-pyridyl)-N'-phenylurea (CPPU), a cytokinin analogue, significantly delayed leaf senescence and maintained cytokinin content of Chinese flowering cabbage during storage. Meanwhile, the expression of an NAC transcriptional activator (BrNAC029) was increased but suppressed by CPPU treatment. Furthermore, BrNAC029 activated the expressions of chlorophyll catabolic genes BrPAO and BrSGR2, cytokinin oxidase gene BrCKX1 and senescence maker gene BrSAG113 by binding to their promoters. Additionally, overexpressions of BrNAC029 in tobacco and Arabidopsis accelerated leaf senescence and up-expressed the related genes. Taken together, it was suggested that BrNAC029 may serve as a transcriptional activator to activate the transcriptions of these related genes to eventually accelerate leaf senescence of Chinese flowering cabbage by promoting chlorophyll degradation and reducing endogenous cytokinin level., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Wax is an acellular structural substance attached to the surface of plant tissues. It forms a protective barrier on the epidermis of plants and plays an important role in resisting abiotic and biotic stresses. In this paper, nonheading Chinese cabbage varieties with and without wax powder were observed using scanning electron microscopy, and the surface of waxy plants was covered with a layer of densely arranged waxy crystals, thus differentiating them from the surface of waxless plants. A genetic analysis showed that wax powder formation in nonheading Chinese cabbage was controlled by a pair of dominant genes. A preliminary bulked segregant analysis sequencing (BSA-seq) assay showed that one gene was located at the end of chromosome A09. Within this interval, we identified BraA09000626, encoding an AP2 transcription factor homologous to Arabidopsis AtSHINE3, and we named it BrSHINE3. By comparing the CDS of the gene in the two parental plants, a 35 bp deletion in the BrSHINE3 gene of waxless plants resulted in a frameshift mutation. Tissue analysis showed that BrSHINE3 was expressed at significantly higher levels in waxy plant rosette stage petioles and bolting stage stems than in the tissues of waxless plants. We speculate that this deletion in BrSHINE3 bases in the waxless material may inhibit wax synthesis. The overexpression of BrSHINE3 in Arabidopsis induced the accumulation of wax on the stem surface, indicating that BrSHINE3 is a key gene that regulates the formation of wax powder in nonheading Chinese cabbage. The analysis of the subcellular localization showed that BrSHINE3 is mainly located in the nucleus and chloroplast of tobacco leaves, suggesting that the gene may function as a transcription factor. Subsequent transcriptome analysis of the homology of BrSHINE3 downstream genes in nonheading Chinese cabbage showed that these genes were downregulated in waxless materials. These findings provide a basis for a better understanding of the nonheading Chinese cabbage epidermal wax synthesis pathway and provide important information for the molecular-assisted breeding of nonheading Chinese cabbage.

Sweet basil (Ocimum basilicum L.) is an important aromatic plant with high edibility and economic value, widely distributed in many regions of the tropics including the south of China. In recent years, environmental problems, especially soil salinization, have seriously restricted the planting and spread of sweet basil. However, the molecular mechanism of the salt stress response in sweet basil is still largely unknown. In this study, seed germination, seedling growth, and chlorophyll synthesis in sweet basil were inhibited under salt stress conditions. Through comparative transcriptome analysis, the gene modules involved in the metabolic processes, oxidative response, phytohormone signaling, cytoskeleton, and photosynthesis were screened out. In addition, the landscape of transcription factors during salt treatment in sweet basil was displayed as well. Moreover, the overexpression of the WRKY transcription factor-encoding gene, ObWRKY16, and the phenylalanine ammonia-lyase-encoding gene, ObPAL2, enhanced the seed germination, seedling growth, and survival rate, respectively, of transgenic Arabidopsis, suggesting that they might be important candidates for the creation of salt-tolerant sweet basil cultivars. Our data enrich the study on salt responses in sweet basil and provide essential gene resources for genetic improvements in sweet basil in the future. [ABSTRACT FROM AUTHOR]

Masson pine (Pinus massoniana) is a core industrial tree species that is used for afforestation in southern China. Previous studies have shown that Auxin Response Factors (ARFs) are involved in the growth and development of various species, but the function of ARFs in Masson pine is unclear. In this research, we cloned and identified Masson pine ARF6 cDNA (PmARF6). The results showed that PmARF6 encodes a protein of 681 amino acids that is highly expressed in female flowers. Subcellular analysis showed that the PmARF6 protein occurred predominantly in the nucleus and cytomembrane of Masson pine cells. Compared with wild-type (WT) Arabidopsis, transgenic Arabidopsis plants overexpressing PmARF6 had fewer rosette leaves, and their flower development was slower. These results suggest that overexpression of PmARF6 may inhibit the flower and leaf development of Masson pine and provide new insights into the underlying developmental mechanism. [ABSTRACT FROM AUTHOR]

Background: Cymbidium is an economically important genus of flowering orchids cultivated in China because of showing graceful leaf shapes and elegant flower coloration. However, the deterioration of the ecological environment and the difficulty of conservation management have become increasing challenges for maintaining its germplasm resources. ARFs are critical transcription factors in the auxin signaling pathway and have been found to play pivotal roles in leaf growth and development in previous studies. However, their functions and mechanisms in Cymbidium goeringii remain to be clarified. Methods: The sequence of the CgARF1 gene was analyzed by bioinformatics. The expression of this gene in different tissues and under IAA treatment was detected by quantitative real-time PCR analysis. The CgARF1 gene was overexpressed in wild-type Arabidopsis and Nicotiana benthamiana via the Agrobacterium infection method. Acetone-ethanol solvent extraction was applied for the determination of chlorophyll contents, and the contents of endogenous hormones were determined using the enzyme-linked immunosorbent assay technique. Results: CgARF1 cloned from C. goeringii 'Songmei' was 2,049 bp in length and encoded 682 amino acids containing three typical domains: a B3 DNA binding domain, an Aux_resp domain and an AUX/IXX family domain. The expression pattern of CgARF1 in different tissues of C. goeringii showed that its expression was highest in the leaves and changed greatly under IAA treatment. Subcellular localization studies showed that the protein was mainly localized in the cell nucleus. CgARF1-overexpressing lines exhibited leaf senescence and a decreased chlorophyll content. Under IAA treatment, CgARF1 regulates the rooting length, rooting number and rooting rate from detached leaves. The levels of endogenous hormones in transgenic leaves were also significantly changed. Conclusion: These results indicated that CgARF1 overexpression is responsive to IAA treatment during leaf development. This study provides a foundation for future research on the function of the ARF gene family in C. goeringii. [ABSTRACT FROM AUTHOR]

Background and aims: The crude extract of the endophyte Paecilomyces variotii known as ZhiNengCong (ZNC) has function of promoting plant growth and enhancing disease resistance and is widely used in China. Our study aims to evaluate the molecular mechanisms of plant growth promotion and disease protection. Methods: We generated transcriptome profiles from ZNC-treated seedlings using RNA sequencing. The function of salicylic acid (SA) in ZNC-mediated immunity was examined using SA biosynthesis and signaling pathway mutants. The concentrations of nitrogen (N) and phosphorus (P) in seedlings under ZNC treatment were measured. The effect of ZNC on the level of the hormone auxin in roots was tested using transgenic plants containing DR5::GFP. Results: ZNC exhibited ultrahigh activity in promoting plant growth and enhancing disease resistance, even at concentrations as low as 1–10 ng/ml. ZNC induced ROS accumulation, callose deposition, and expression of PR genes. SA biosynthesis and signaling pathways were required for the ZNC-mediated defense response. Moreover, in improving plant growth, ZNC increased the level of auxin in root tips and regulated the absorption of N and P. Conclusion: According to these results, ZNC is a highly effective plant elicitor that promotes plant growth by inducing auxin accumulation at the root tip at low concentrations and enhances plant disease resistance by activating the SA signaling pathway at high concentrations. [ABSTRACT FROM AUTHOR]

Sapium sebiferum (L.) Roxb is one of the most important oil trees in China. Diacylglycerol acyltransferases (DGATs) esterify sn-1, 2-diacylglycerol with a long-chain fatty acyl-CoA, the last step and the rate-limiting step of triacylglycerol (TAG) biosynthesis in prokaryotic and eukaryotic organisms. At least 74 DGAT2 sequences from 61 organisms have been identified, but the SsDGAT2 gene had not been reported to date. To clarify the function of SsDGAT2, we cloned the CDS (rapid amplification of cDNA end) of SsDGAT2 by RACE technology. The full-length CDS of SsDGAT2 contains 1011 bp and encodes a protein of 336 amino acids. Recombinant SsDGAT2 restored TAG biosynthesis to the yeast strain Saccharomyces cerevisiae H1246 TAG-deficient mutant and preferentially incorporated unsaturated C18 fatty acids into lipids. To investigate the biotechnological potential of SsDGAT2, it was expressed under the control of the 35S promoter in Arabidopsis Col-4. The oleic acid content increased by 50 % in transgenic plants relative to the control. The results indicated that most of the oleic acid increase was at the expense of linolenic acid (18:3) content, which suggests that high-oleic-acid-content seeds can be created by the overexpression of SsDGAT2 in S. sebiferum (L.) Roxb. [ABSTRACT FROM AUTHOR]

Rice is a facultative short-day plant (SDP), and the regulatory pathways for flowering time are conserved, but functionally modified, in Arabidopsis and rice. Heading date 1 (Hd1), an ortholog of Arabidopsis CONSTANS (CO), is a key regulator that suppresses flowering under long-day conditions (LDs), but promotes flowering under short-day conditions (SDs) by influencing the expression of the florigen gene Heading date 3a (Hd3a). Another key regulator, Early heading date 1 (Ehd1), is an evolutionarily unique gene with no orthologs in Arabidopsis, which acts as a flowering activator under both SD and LD by promoting the rice florigen genes Hd3a and RICE FLOWERING LOCUST 1 (RFT1). Here, we report the isolation and characterization of the flowering regulator eading ate epressor1 (HDR1) in rice. The hdr1 mutant exhibits an early flowering phenotype under natural LD in a paddy field in Beijing, China (39°54'N, 116°23'E), as well as under LD but not SD in a growth chamber, indicating that HDR1 may functionally regulate flowering time via the photoperiod-dependent pathway. HDR1 encodes a nuclear protein that is most active in leaves and floral organs and exhibits a typical diurnal expression pattern. We determined that HDR1 is a novel suppressor of flowering that upregulates Hd1 and downregulates Ehd1, leading to the downregulation of Hd3a and RFT1 under LDs. We have further identified an HDR1-interacting kinase, OsK4, another suppressor of rice flowering under LDs. OsK4 acts similarly to HDR1, suppressing flowering by upregulating Hd1 and downregulating Ehd1 under LDs, and OsK4 can phosphorylate HD1 with HDR1 presents. These results collectively reveal the transcriptional regulators of Hd1 for the day-length-dependent control of flowering time in rice. [ABSTRACT FROM AUTHOR]