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[前沿资讯 ] 华盛顿州立大学研究人员开发出能导电的新型棉纤维 进入全文
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研究人员开发出一种新型纤维，它既有棉花的柔韧性，又有聚合物聚苯胺的导电性。这种创新材料在《碳水化合物聚合物》（Carbohydrate Polymers）期刊中做了详细介绍，它显示出了制造可穿戴电子纺织品的潜力，可用于健康监测和危险暴露检测等应用。 华盛顿州立大学开发的一种单股纤维同时具有棉花的柔韧性和一种名为聚苯胺的聚合物的导电性，显示出在可穿戴电子纺织品方面的巨大潜力。华盛顿州立大学的研究人员用一个为 LED 灯供电的系统和另一个感应氨气的系统测试了这种纤维，并在《碳水化合物聚合物》杂志上详细介绍了他们的研究成果。 华盛顿州立大学纺织品研究员、该研究的通讯作者刘航（音译）说："我们将一种纤维分为两部分：一部分是传统的棉花：柔韧性和强度足以满足日常使用，而另一面则是导电材料。棉花可以支撑导电材料，而导电材料可以提供所需的功能。" 可穿戴技术的潜在应用 虽然还需要更多的开发工作，但研究人员的想法是将这样的纤维集成到服装中，作为带有柔性电路的传感器贴片。这些贴片可以成为消防员、士兵或处理化学品的工人制服的一部分，以检测是否接触到危险物质。其他应用还包括健康监测或运动衬衫，它们比目前的健身监测器能做得更多。 刘说："我们现在有一些智能可穿戴设备，比如智能手表可以跟踪你的运动和人体生命体征，但我们希望将来你的日常服装也能实现这些功能。时尚并不像很多人认为的那样只是颜色和款式，时尚就是科学本身。" 技术挑战与解决方案 在这项研究中，华盛顿州立大学团队努力克服将导电聚合物与棉纤维素混合的难题。聚合物是一种具有重复模式的大分子物质。在这种情况下，研究人员使用了聚苯胺（又称 PANI），这是一种具有导电性能的合成聚合物，已被用于印刷电路板制造等应用中。 虽然聚苯胺本身具有导电性，但它比较脆，无法制成纺织品纤维。为了解决这个问题，西悉尼大学的研究人员将从回收的 T 恤衫中提取的棉纤维素溶解到一种溶液中，并将导电聚合物溶解到另一种单独的溶液中。然后将这两种溶液并排合并在一起，挤出材料制成一根纤维。 结果显示界面结合良好，这意味着不同材料的分子在拉伸和弯曲过程中都能保持在一起，在棉纤维素和聚苯胺的界面上实现适当的混合是一个微妙的平衡。 刘说："我们希望这两种溶液能够发挥作用，这样当棉花和导电聚合物相互接触时，它们就会在一定程度上混合在一起，形成一种粘合剂，但我们又不希望它们混合得太多，否则导电性能就会降低。" 参考文献：《用于可穿戴电子纺织品的纤维素基导电复合纤维的新型结构设计》，作者：Wangcheng Liu、Hang Liu、Zihui Zhao、Dan Liang、Wei-Hong Zhong 和 Jinwen Zhang，2023 年 8 月 18 日，《碳水化合物聚合物》。
[前沿资讯 ] 超一千三百个水稻、玉米、大豆、棉花新品种获审定通过——中国农作物品种创新有新突破 进入全文
人民日报海外版
优质绿色水稻、耐密宜机收玉米、高油高产大豆——近日，农业农村部发布品种审定公告，第五届国家农作物品种审定委员会（以下简称国家品审委）根据《种子法》《主要农作物品种审定办法》有关规定，审定通过了1304个水稻、玉米、大豆、棉花新品种。 这些新品种有啥特点？对保障粮食安全有何帮助？农业农村部有关负责人表示，从审定品种情况看，相关作物品种创新取得了一系列新进展、新突破，这些品种推广应用将有利于持续提升我国粮食大面积单产和品质水平。 水稻是此次新品种中数量较多的一类，共409个，优质绿色是其突出特点。此次审定通过米质达到国标1级优质米品种50个，较上年增加6个；兼具高产、优质、绿色的“三好品种”28个，同比增加6个。 由湖南杂交水稻研究中心育种并提出申请的“西子3号”是其中之一。中国工程院院士、湖南省农业科学院党委书记柏连阳介绍，经检测，“西子3号”在区域试验中的糙米镉含量为每千克0.000至0.098毫克，低于每千克0.2毫克的国家限量标准。“作为籼型常规稻品种，‘西子3号’可在长江中下游做双季晚稻种植，将有利于部分受重金属污染的地区解决‘镉大米’问题，提升我国粮食安全的保障能力。”柏连阳说。 大豆是另一个重要品类。数据显示，此次审定通过17个高油高产大豆新品种，占比达到1/5，亩产最高达到240公斤，含油率最高达到22.97%，同时筛选推荐了7个适合大豆玉米带状复合种植的大豆品种。 国家品审委负责人介绍，围绕加强高油大豆品种培育和大面积单产提升，国家品审委日前对外发布《国家级大豆品种审定标准（2023年修订）》。此次标准修订提高了品种DNA指纹差异要求，推动解决品种同质化问题，同时提高了品种产量、品质要求以及品种抗病性要求。 “聚焦大豆品种审定，我们还将在对照品种、种植密度、试验布局等方面对品种试验实施方案进行完善。”上述负责人说，明年将先行调整北方春大豆中早熟和中晚熟组、黄淮海夏大豆南片等生态区组对照品种，引导高产大豆品种选育；在2022年大豆品种试验种植密度普遍提高10%的基础上，明年将北方春大豆早熟区、黄淮海夏大豆北片等部分生态区试验种植密度再提高10%，引导耐密大豆品种选育；按照主要农作物品种审定办法规定，同一生态类型区试验点，国家级不少于10个，目前试验点一般在10-13个，明年将北方春大豆等生态区试验点数增加10%以上，进一步强化对品种稳产性的试验评价。 此次审定推出的优质高产新品种还包括764个玉米品种、51个棉花品种。具体来看：审定通过15个籽粒机收品种，覆盖三大主产区，籽粒含水量平均为23.7%，同比下降0.56个百分点；耐密品种选育初现苗头，郑原玉333、郑品玉608等品种在西北种植密度每亩可达6000株以上。审定通过纤维品质优质I型和II型品种26个，占比达到51%；生育期小于110天且品质不低于Ⅱ型的短季棉品种2个，可用于黄河流域棉区麦后直播棉种植和长江流域棉区扩种油菜茬口衔接。 农业农村部表示，国家品审委按照种业振兴市场净化行动安排部署，正组织持续推进品种审定绿色通道和联合体试验整治，不断规范品种审定试验，同时加快修订小麦、棉花品种审定标准，多措并举为粮油等主要作物大面积单产提升提供有力品种支撑。
[前沿资讯 ] How a moth’s taste preferences change with age——Researchers have characterised the molecular basis for the change in food selection among cotton bollworms that occurs between their larval and adult stages. 进入全文
ELIFE
The larvae and adult forms of the cotton bollworm (Helicoverpa armigera) adopt different sugar-sensing systems to satisfy their requirements for food selection, according to new research. Published today as a Reviewed Preprint in eLife, the study is described as important by the editors, who say it offers convincing evidence that two different gustatory receptors for sugar sensing underlie the change in diet preference between the larval and adult cotton bollworm. The findings, combined with further research, could suggest a new approach for pest control to increase crop yields across the globe. The cotton bollworm is a notorious, world-wide crop pest that contributes to approximately USD$3bn worth of economic loss every year. In its juvenile, larval stage the cotton bollworm mostly feeds on the leaves, flower buds and fruits of plants, which have a relatively low sugar concentration. As an adult, it mostly feeds on the sugar-rich nectar of plants. Previous studies have shown that the cotton bollworm has external gustatory sensory neurons (GSNs) – specialised nerve cells responsible for detecting and transmitting taste signals to the brain – that are sensitive to sucrose and fructose. In larvae, these GSNs are located in specialised structures around their mouth, and in adults they are found in their antennae, the tarsi (the segments of the leg that are furthest from the body) and a specialised feeding structure called the proboscis, which serves a similar function as the human tongue. “The larval and adult diets of the cotton bollworm vary dramatically in their variety and concentration of sugars. Sucrose is the major sugar found in plant tissues, whereas nectar mainly contains sucrose, fructose and glucose,” explains lead author Shuai-Shuai Zhang, a PhD student at the State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China. “We aimed to characterise the molecular basis for the change in diet seen between the cotton bollworm’s two life phases.” Zhang and colleagues first compared the electrophysiological and behavioural responses of cotton bollworm larvae and adults to seven sugars found in plants, including sucrose, fructose and glucose. They confirmed that both larvae and adults have sugar-detecting GSNs, but that their response profile, intensity and sensitivity differed markedly. The sugar GSNs in larvae responded strongly to sucrose with high sensitivity – between 100–1,000 times more sensitive to sucrose than adult GSNs, which responded to sucrose, fucose and fructose with lower intensity and sensitivity. This high sensitivity in larvae may help them locate sucrose in the sugar-sparse tissues of plants. Next, the team analysed the expression and function of nine candidate sugar gustatory receptor (GR) genes in larval and adult taste organs; Gr4–Gr12 inclusively. Since the function of Gr9 is known, they tested the function of other eight GRs using Xenopus oocytes – the unfertilised eggs of the African clawed frog, which are widely used in scientific research as they are large and relatively easy to manipulate. The team inserted DNA sequences for each GR gene into an individual oocyte, and then tested each oocyte’s response to 11 different sugar compounds. Most oocytes had no response, but the oocytes expressing Gr10 and Gr6 were responsive to one or more sugars, indicating their role in food recognition. Gr10 was found to be tuned to sucrose specifically, whereas Gr6 responded to sucrose, fucose and fructose. Finally, Zhang and colleagues used CRISPR/Cas9 DNA modifying techniques to create two homozygous mutants of cotton bollworms for Gr6 and Gr10, respectively – meaning they do not possess the function of the Gr6 or Gr10 gene any more. The team sought to identify any changes in the electrophysiological and behavioural responses of the mutant larvae and adults to sugars compared to typical cotton bollworms. From their analysis, the team determined that Gr10 plays a key role in sucrose reception by the sugar GSNs in larvae, and mediates the larvae’s preference for sucrose. On the other hand, Gr6 is responsible for sensing sucrose, fucose and fructose in the GSNs of the adult cotton bollworm. Taken together, the results demonstrate that larval and adult cotton bollworms use different gustatory receptor genes to detect sucrose in food. Larvae mainly use Gr10 to detect the low amount of sucrose found in plant tissues, whereas adults primarily use Gr6 to detect a variety of sugars with high content, including sucrose in nectar. Both the authors and the editors note that, to thoroughly reveal the mechanisms of sugar sensing to design a new approach for pest control, it is crucial to first comprehensively study the function of all of the GRs involved in sucrose sensation. “We’ve reported the molecular basis of sucrose reception in the eternal taste neurons of the cotton bollworm, and discovered that different taste receptors underlie the difference in food selection between the adult and larval stages,” concludes senior author Chen-Zhu Wang, a professor at the State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences. “GRs closely associated with Gr10 and Gr6 are also found in other moth and butterfly species. We therefore speculate that similar sugar-sensing mechanisms may also exist in these species, which is worth verifying with future research.”
[学术文献 ] GhMYB30-GhMUR3 affects fiber elongation and secondary wall thickening in cotton 进入全文
PLANT JOURNAL
Xyloglucan, an important hemicellulose, plays a crucial role in maintaining cell wall structure and cell elongation. However, the effects of xyloglucan on cotton fiber development are not well understood. GhMUR3 encodes a xyloglucan galactosyltransferase that is essential for xyloglucan synthesis and is highly expressed during fiber elongation. In this study, we report that GhMUR3 participates in cotton fiber development under the regulation of GhMYB30. Overexpression GhMUR3 affects the fiber elongation and cell wall thickening. Transcriptome showed that the expression of genes involved in secondary cell wall synthesis was prematurely activated in OE-MUR3 lines. In addition, GhMYB30 was identified as a key regulator of GhMUR3 by Y1H, Dual-Luc, and electrophoretic mobility shift assay (EMSA) assays. GhMYB30 directly bound the GhMUR3 promoter and activated GhMUR3 expression. Furthermore, DAP-seq of GhMYB30 was performed to identify its target genes in the whole genome. The results showed that many target genes were associated with fiber development, including cell wall synthesis-related genes, BR-related genes, reactive oxygen species pathway genes, and VLCFA synthesis genes. It was demonstrated that GhMYB30 may regulate fiber development through multiple pathways. Additionally, GhMYB46 was confirmed to be a target gene of GhMYB30 by EMSA, and GhMYB46 was significantly increased in GhMYB30-silenced lines, indicating that GhMYB30 inhibited GhMYB46 expression. Overall, these results revealed that GhMUR3 under the regulation of GhMYB30 and plays an essential role in cotton fiber elongation and secondary wall thickening. Additionally, GhMYB30 plays an important role in the regulation of fiber development and regulates fiber secondary wall synthesis by inhibiting the expression of GhMYB46.
[学术文献 ] Identification of candidate genes in cotton associated with specific seed traits and their initial functional characterization in Arabidopsis 进入全文
PLANT JOURNAL
Oilseed crops are used to produce vegetable oil to satisfy the requirements of humans and livestock. Cotton (Gossypium spp.) is of great economic value because it is used as both an important textile commodity and a nutrient-rich resource. Cottonseed oil is rich in polyunsaturated fatty acids and does not contain trans fatty acids; hence, it is considered a healthy vegetable oil. However, research on the genetic basis for cottonseed protein content, oil production, and fatty acid composition is lacking. Here, we investigated the protein content, oil content, and fatty acid composition in terms of oleic acid (C18:1) and linoleic acid (C18:2) in mature cottonseeds from 318 Gossypium hirsutum accessions. Moreover, we examined the dynamic change of protein content and lipid composition including palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and linolenic acid (C18:3) in developing seeds from 258 accessions at 10 and 20 days post-anthesis. Then, we conducted a genome-wide association study and identified 152 trait-associated loci and 64 candidate genes responsible for protein and oil-related contents in mature cottonseeds and ovules. Finally, six candidate genes were experimentally validated to be involved in the regulation of fatty acid biosynthesis through heterologous expression in Arabidopsis. These results comprise a solid foundation for expanding our understanding of lipid biosynthesis in cotton, which will help breeders manipulate protein and oil contents to make it a fully developed 'fiber, food, and oil crop'.
[学术文献 ] Expressed genes and their new alleles identification during fibre elongation reveal the genetic factors underlying improvements of fibre length in cotton 进入全文
PLANT BIOTECHNOLOGY JOURNAL
Interspecific breeding in cotton takes advantage of genetic recombination among desirable genes from different parental lines. However, the expression new alleles (ENAs) from crossovers within genic regions and their significance in fibre length (FL) improvement are currently not understood. Here, we generated resequencing genomes of 191 interspecific backcross inbred lines derived from CRI36 (Gossypium hirsutum) x Hai7124 (Gossypium barbadense) and 277 dynamic fibre transcriptomes to identify the ENAs and extremely expressed genes (eGenes) potentially influencing FL, and uncovered the dynamic regulatory network of fibre elongation. Of 35 420 eGenes in developing fibres, 10 366 ENAs were identified and preferentially distributed in chromosomes subtelomeric regions. In total, 1056-1255 ENAs showed transgressive expression in fibres at 5-15 dpa (days post-anthesis) of some BILs, 520 of which were located in FL-quantitative trait locus (QTLs) and GhFLA9 (recombination allele) was identified with a larger effect for FL than GhFLA9 of CRI36 allele. Using ENAs as a type of markers, we identified three novel FL-QTLs. Additionally, 456 extremely eGenes were identified that were preferentially distributed in recombination hotspots. Importantly, 34 of them were significantly associated with FL. Gene expression quantitative trait locus analysis identified 1286, 1089 and 1059 eGenes that were colocalized with the FL trait at 5, 10 and 15 dpa, respectively. Finally, we verified the Ghir_D10G011050 gene linked to fibre elongation by the CRISPR-cas9 system. This study provides the first glimpse into the occurrence, distribution and expression of the developing fibres genes (especially ENAs) in an introgression population, and their possible biological significance in FL.
