Cotton (Gossypium hirsutum) fibers are the highly elongated and thickened single-cell trichomes on the seed epidermis. However, little is known about the molecular base of fiber cell wall thickening ...in detail.
In this study, a cotton NAC transcription factor (GhFSN1) that is specifically expressed in secondary cell wall (SCW) thickening fibers was functionally characterized. The GhFSN1 transgenic cotton plants were generated to study how FSN1 regulates fiber SCW formation.
Up-regulation of GhFSN1 expression in cotton resulted in an increase in SCW thickness of fibers but a decrease in fiber length. Transcriptomic analysis revealed that GhFSN1 activates or represses numerous downstream genes. GhFSN1 has the ability to form homodimers, binds to its promoter to activate itself, and might be degraded by the ubiquitin-mediated proteasome pathway. The direct targets of GhFSN1 include the fiber SCW-related GhDUF231L1, GhKNL1, GhMYBL1, GhGUT1 and GhIRX12 genes. GhFSN1 binds directly to a consensus sequence (GhNBS), (C/T)(C/G/T)TN(A/T)(G/T)(A/C/G)(A/G)(A/T/G)(A/T/G)AAG, which exists in the promoters of these SCW-related genes.
Our data demonstrate that GhFSN1 acts as a positive regulator in controlling SCW formation of cotton fibers by activating its downstream SCW-related genes. Thus, these findings give us novel insights into comprehensive understanding of GhFSN1 function in fiber development.
Diseases such as Fusarium wilt caused by Fusarium oxysporum f.sp. vasinfectum (FOV), a soil borne fungal pathogen, represent expanding threats to cotton (Gossypium spp.) production around the world. ...For over a decade, FOV race 4 (FOV4) has adversely impacted cotton production in California's San Joaquin Valley causing plant wilt and death. With this disease formally identified in 2019 in New Mexico and in 2017 in El Paso, TX region in proximity to the High Plains of west Texas-the largest Upland cotton producing region in the USA, the need to expand the genetic base of Upland (G. hirsutum L.) cotton and develop cultivars resistant/tolerant to FOV4 has become urgent. Our previous research in Pima (G. barbadense L.) cotton identified high levels of resistance to FOV4 in 'Pima S-6' germplasm, and our program publicly released Pima germplasm with improved FOV4 resistance. However, the search for resistant Upland cotton has proved more challenging compared to the effort in Pima. More than 1000 Upland accessions from the USDA-ARS Cotton Germplasm Collection were evaluated for reaction to FOV4 in artificial-greenhouse conditions and in naturally infested grower fields. Less than 0.1% of the tested accessions were selected to develop highly resistant FOV4 progeny. Two sources (NM12Y1004-NM12Y1005 and SA-3208) of Asiatic breeding origin were identified with tolerance to FOV4 and used to introgress and increase resistance. Pedigree information from other parental lines used to develop progeny revealed their sources to be exotic and wild Upland germplasm. That is triple/multiple crosses included the origin of these obsolete SA cultivars 'Auburn M', 'DES 920', 'MARSPD202085', 'S.N.0503-1', PD 2165, and 'Stoneville 14', among others. A range of severity of foliar symptoms, vascular root staining, and plant mortality occurred in the infested fields based on tested accessions and observations of susceptible germplasm/cultivar-checks, indicating moderate to severe inoculum levels with the sites. Many FOV4 infected Upland cultivars typically showed fewer leaf symptoms and much lower plant mortality in early stages of the disease compared to Pima cultivars. The inheritance of FOV4 resistance/tolerance in Upland cotton ranges from recessive to intermediate, unlike in Pima cotton where resistance seems to be dominant or more complete in the host plant. Highly resistant/tolerant Upland breeding lines were developed from this breeding research effort and will be publicly released to reduce the vulnerability of the cotton industry to this pathogen.
A single seed is more than just the promise of a plant. In rural south India, seeds represent diverging paths toward a sustainable livelihood. Development programs and global agribusiness promote ...genetically modified seeds and organic certification as a path toward more sustainable cotton production, but these solutions mask a complex web of economic, social, political, and ecological issues that may have consequences as dire as death. In Cultivating Knowledge anthropologist Andrew Flachs shows how rural farmers come to plant genetically modified or certified organic cotton, sometimes during moments of agrarian crisis. Interweaving ethnographic detail, discussions of ecological knowledge, and deep history, Flachs uncovers the unintended consequences of new technologies, which offer great benefits to some-but at others' expense. Flachs shows that farmers do not make simple cost-benefit analyses when evaluating new technologies and options. Their evaluation of development is a complex and shifting calculation of social meaning, performance, economics, and personal aspiration. Only by understanding this complicated nexus can we begin to understand sustainable agriculture. By comparing the experiences of farmers engaged with these mutually exclusive visions for the future of agriculture, Cultivating Knowledge investigates the human responses to global agrarian change. It illuminates the local impact of global changes: the slow, persistent dangers of pesticides, inequalities in rural life, the aspirations of people who grow fibers sent around the world, the place of ecological knowledge in modern agriculture, and even the complex threat of suicide. It all begins with a seed.
Display omitted
•ZnO-coated cotton fabric materials were fabricated by rapid microwave method.•The structures of the ZnO crystals varied according to the seeding solution pH.•The ZnO-coated cotton ...fabric showed excellent UV protection property (UPF 50+).•The wetting behavior of the fabric surfaces was affected by the ZnO coating layer.•Self-cleaning activity was verified by the removal of coffee stains under UV light.
A new self-cleaning cotton fabric coated with zinc oxide (ZnO) was obtained via a facile and effective microwave method. The solution pH was a key factor in determining the morphology of ZnO crystal growth on the cotton fibers: rod structures were apt to be formed at pH 4–5, whereas flake and flower-like structures were preferentially formed at higher solution pHs of 6–7 and 10–11, respectively. It is proved that the photocatalytic and wettability performances of ZnO could be efficiently transferred to cotton fabric, leading to a preeminent UV-blocking and self-cleaning cotton fabric. The identified UV protection factors (UPFs) indicate the excellent UV-blocking properties of the ZnO-coated textile fabric synthesized at pH 6–7, 8–9 and 10–11 with UPFs of 222.52, 162.68 and 202.57, respectively. The ZnO coating layer on the cotton fabric significantly improved the wetting behavior of the fabric, such as water absorption speed, thereby affording a self-cleaning ability for the ZnO-coated cotton fabrics. This ability was checked according to the removal degree of coffee stain under UV irradiation at different humidities (30–90% RH). The coffee stains on the ZnO-coated cotton fabrics were almost removed after 15h without needing any water or detergent and the highest removal effect was observed at 90% humidity.
Summary
Cotton fibre is a unicellular seed trichome, and lint fibre initials per seed as a factor determines fibre yield. However, the mechanisms controlling fibre initiation from ovule epidermis are ...not understood well enough. Here, with single‐cell RNA sequencing (scRNA‐seq), a total of 14 535 cells were identified from cotton ovule outer integument of Xu142_LF line at four developmental stages (1.5, 1, 0.5 days before anthesis and the day of anthesis). Three major cell types, fibre, non‐fibre epidermis and outer pigment layer were identified and then verified by RNA in situ hybridization. A comparative analysis on scRNA‐seq data between Xu142 and its fibreless mutant Xu142 fl further confirmed fibre cluster definition. The developmental trajectory of fibre cell was reconstructed, and fibre cell was identified differentiated at 1 day before anthesis. Gene regulatory networks at four stages revealed the spatiotemporal pattern of core transcription factors, and MYB25‐like and HOX3 were demonstrated played key roles as commanders in fibre differentiation and tip‐biased diffuse growth respectively. A model for early development of a single fibre cell was proposed here, which sheds light on further deciphering mechanism of plant trichome and the improvement of cotton fibre yield.
With scRNA‐seq, cotton fibre cell was identified differentiated at −1 DPA. It further refines the spatiotemporal patterns of two command genes, MYB25‐like and HOX3, who determine fibre differentiation and tip‐biased diffuse growth respectively.
Long noncoding RNAs (lncRNAs) are transcripts of at least 200 bp in length, possess no apparent coding capacity and are involved in various biological regulatory processes. Until now, no systematic ...identification of lncRNAs has been reported in cotton (Gossypium spp.).
Here, we describe the identification of 30 550 long intergenic noncoding RNA (lincRNA) loci (50 566 transcripts) and 4718 long noncoding natural antisense transcript (lncNAT) loci (5826 transcripts). LncRNAs are rich in repetitive sequences and preferentially expressed in a tissue-specific manner. The detection of abundant genome-specific and/or lineage-specific lncRNAs indicated their weak evolutionary conservation. Approximately 76% of homoeologous lncRNAs exhibit biased expression patterns towards the At or Dt subgenomes. Compared with protein-coding genes, lncRNAs showed overall higher methylation levels and their expression was less affected by gene body methylation.
Expression validation in different cotton accessions and coexpression network construction helped to identify several functional lncRNA candidates involved in cotton fibre initiation and elongation. Analysis of integrated expression from the subgenomes of lncRNAs generating miR397 and its targets as a result of genome polyploidization indicated their pivotal functions in regulating lignin metabolism in domesticated tetraploid cotton fibres.
This study provides the first comprehensive identification of lncRNAs in Gossypium.
Achieving rapid definitive hemostasis is essential to ensure survival of patients with massive bleeding in pre-hospital care. It is however challenging to develop hemostatic agents or dressings that ...simultaneously deliver a fast, long-lasting and safe treatment of hemorrhage. Here, we integrate meso-/micro-porosity, blood coagulation and stability into a flexible zeolite-cotton hybrid hemostat. We employ an on-site template-free growth route that tightly binds mesoporous single-crystal chabazite zeolite onto the surface of cotton fibers. This hemostatic material maintains high procoagulant activity after water flow treatment. Chabazite particles are firmly anchored onto the cotton surface with < 1% leaching after 10 min of sonication. The as-synthesized hemostatic device has superior hemostatic performance over most other clay or zeolite-based inorganic hemostats, in terms of higher procoagulant activity, minimized loss of active components and better scalability for practical applications (a hemostatic T-shirt is hereby demonstrated as an example).
In this study, the GhKNL1 (KNOTTED1-LIKE) gene, encoding a classical class II KNOX protein was identified in cotton (Gossypium hirsutum). GhKNL1 was preferentially expressed in developing fibres at ...the stage of secondary cell wall (SCW) biosynthesis. GhKNL1 was localized in the cell nucleus, and could interact with GhOFP4, as well as AtOFP1, AtOFP4, and AtMYB75. However, GhKNL1 lacked transcriptional activation activity. Dominant repression of GhKNL1 affected fibre development of cotton. The expression levels of genes related to fibre elongation and SCW biosynthesis were altered in transgenic fibres of cotton. As a result, transgenic cotton plants produced aberrant, shrunken, and collapsed fibre cells. Length and cell-wall thickness of fibres of transgenic cotton plants were significantly reduced compared with the wild type. Furthermore, overexpression and dominant repression of GhKNL1 in Arabidopsis resulted in a reduction in interfascicular fibre cell-wall thickening of basal stems of transgenic plants. Complementation revealed that GhKNL1 rescued the defective phenotype of Arabidopsis knat7 mutant in some extent. These data suggest that GhKNL1, as a transcription factor, participates in regulating fibre development of cotton.
Textiles made from cotton fibers are flammable and thus often include flame retardant additives for consumer safety. Transgressive segregation in multi-parent populations facilitates new combinations ...of alleles of genes and can result in traits that are superior to those of any of the parents. A screen of 257 recombinant inbred lines from a multi-parent advanced generation intercross (MAGIC) population for naturally enhance flame retardance (FR) was conducted. All eleven parents, like all conventional white fiber cotton cultivars produce flammable fabric. MAGIC recombinant inbred lines (RILs) that produced fibers with significantly lower heat release capacities (HRC) as measured by microscale combustion calorimetry (MCC) were identified and the stability of the phenotypes of the outliers were confirmed when the RILs were grown at an additional location. Of the textiles fabricated from the five superior RILs, four exhibited the novel characteristic of inherent flame resistance. When exposed to open flame by standard 45° incline flammability testing, these four fabrics self-extinguished. To determine the genetic architecture of this novel trait, linkage, epistatic and multi-locus genome wide association studies (GWAS) were conducted with 473k SNPs identified by whole genome sequencing (WGS). Transcriptomes of developing fiber cells from select RILs were sequenced (RNAseq). Together, these data provide insight into the genetic mechanism of the unexpected emergence of flame-resistant cotton by transgressive segregation in a breeding program. The incorporation of this trait into global cotton germplasm by breeding has the potential to greatly reduce the costs and impacts of flame-retardant chemicals.
PDF
