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991.
992.
Coralie E. Salesse‐Smith Robert E. Sharwood Florian A. Busch David B. Stern 《Plant biotechnology journal》2020,18(6):1409-1420
Many C4 plants, including maize, perform poorly under chilling conditions. This phenomenon has been linked in part to decreased Rubisco abundance at lower temperatures. An exception to this is chilling‐tolerant Miscanthus, which is able to maintain Rubisco protein content under such conditions. The goal of this study was to investigate whether increasing Rubisco content in maize could improve performance during or following chilling stress. Here, we demonstrate that transgenic lines overexpressing Rubisco large and small subunits and the Rubisco assembly factor RAF1 (RAF1‐LSSS), which have increased Rubisco content and growth under control conditions, maintain increased Rubisco content and growth during chilling stress. RAF1‐LSSS plants exhibited 12% higher CO2 assimilation relative to nontransgenic controls under control growth conditions, and a 17% differential after 2 weeks of chilling stress, although assimilation rates of all genotypes were ~50% lower in chilling conditions. Chlorophyll fluorescence measurements showed RAF1‐LSSS and WT plants had similar rates of photochemical quenching during chilling, suggesting Rubisco may not be the primary limiting factor that leads to poor performance in maize under chilling conditions. In contrast, RAF1‐LSSS had improved photochemical quenching before and after chilling stress, suggesting that increased Rubisco may help plants recover faster from chilling conditions. Relatively increased leaf area, dry weight and plant height observed before chilling in RAF1‐LSSS were also maintained during chilling. Together, these results demonstrate that an increase in Rubisco content allows maize plants to better cope with chilling stress and also improves their subsequent recovery, yet additional modifications are required to engineer chilling tolerance in maize. 相似文献
993.
994.
Jonathan Hurtado Dhiraj Acharya Huafang Lai Haiyan Sun Somanath Kallolimath Herta Steinkellner Fengwei Bai Qiang Chen 《Plant biotechnology journal》2020,18(1):266-273
Chikungunya virus (CHIKV) is a mosquito‐transmitted alphavirus, and its infection can cause long‐term debilitating arthritis in humans. Currently, there are no licensed vaccines or therapeutics for human use to combat CHIKV infections. In this study, we explored the feasibility of using an anti‐CHIKV monoclonal antibody (mAb) produced in wild‐type (WT) and glycoengineered (?XFT) Nicotiana benthamiana plants in treating CHIKV infection in a mouse model. CHIKV mAb was efficiently expressed and assembled in plant leaves and enriched to homogeneity by a simple purification scheme. While mAb produced in ?XFT carried a single N‐glycan species at the Fc domain, namely GnGn structures, WT produced mAb exhibited a mixture of N‐glycans including the typical plant GnGnXF3 glycans, accompanied by incompletely processed and oligomannosidic structures. Both WT and ?XFT plant‐produced mAbs demonstrated potent in vitro neutralization activity against CHIKV. Notably, both mAb glycoforms showed in vivo efficacy in a mouse model, with a slight increased efficacy by the ?XFT‐produced mAbs. This is the first report of the efficacy of plant‐produced mAbs against CHIKV, which demonstrates the ability of using plants as an effective platform for production of functionally active CHIKV mAbs and implies optimization of in vivo activity by controlling Fc glycosylation. 相似文献
995.
Suzanne M. Marselis Katharine Abernethy Alfonso Alonso John Armston Timothy R. Baker Jean‐Francois Bastin Jan Bogaert Doreen S. Boyd Pascal Boeckx David F. R. P. Burslem Robin Chazdon David B. Clark David Coomes Laura Duncanson Steven Hancock Ross Hill Chris Hopkinson Elizabeth Kearsley James R. Kellner David Kenfack Nicolas Labrire Simon L. Lewis David Minor Herv Memiaghe Abel Monteagudo Reuben Nilus Michael O'Brien Oliver L. Phillips John Poulsen Hao Tang Hans Verbeeck Ralph Dubayah 《Global Ecology and Biogeography》2020,29(10):1799-1816
996.
997.
Henrik Gislason Jeremy Collie Brian R. MacKenzie Anders Nielsen Maria de Fatima Borges Teresa Bottari Corina Chaves Andrey V. Dolgov Jakov Dul
i Daniel Duplisea Heino O. Fock Didier Gascuel Luís Gil de Sola Jan Geert Hiddink Remment ter Hofstede Igor Isajlovi Jnas Pll Jonasson Ole Jrgensen Kristjn Kristinsson Gudrun Marteinsdottir Hicham Masski Sanja Mati‐Skoko Mark R. Payne Melita Peharda Jakup Reinert Jn Slmundsson Cristina Silva Lilja Stefansdottir Francisco Velasco Nedo Vrgo
《Global Ecology and Biogeography》2020,29(5):842-856
998.
999.
1000.
Shi Zhenjie Zheng Qianjiao Sun Xiaoyang Xie Fuchun Zhao Jian Zhang Gaoyun Zhao Wei Guo Zhixin Ariunzul Ariuka Fahad Shah Adnan Muhammad Qin Dong Saud Shah Yajun Chen 《BMC plant biology》2020,20(1):1-15
Kernel weight and morphology are important traits affecting cereal yields and quality. Dissecting the genetic basis of thousand kernel weight (TKW) and its related traits is an effective method to improve wheat yield. In this study, we performed quantitative trait loci (QTL) analysis using recombinant inbred lines derived from the cross ‘PuBing3228 × Gao8901’ (PG-RIL) to dissect the genetic basis of kernel traits. A total of 17 stable QTLs related to kernel traits were identified, notably, two stable QTLs QTkw.cas-1A.2 and QTkw.cas-4A explained the largest portion of the phenotypic variance for TKW and kernel length (KL), and the other two stable QTLs QTkw.cas-6A.1 and QTkw.cas-7D.2 contributed more effects on kernel width (KW). Conditional QTL analysis revealed that the stable QTLs for TKW were mainly affected by KW. The QTLs QTkw.cas-7D.2 and QKw.cas-7D.1 associated with TKW and KW were delimited to the physical interval of approximately 3.82 Mb harboring 47 candidate genes. Among them, the candidate gene TaFT-D1 had a 1 bp insertions/deletion (InDel) within the third exon, which might be the reason for diversity in TKW and KW between the two parents. A Kompetitive Allele-Specific PCR (KASP) marker of TaFT-D1 allele was developed and verified by PG-RIL and a natural population consisted of 141 cultivar/lines. It was found that the favorable TaFT-D1 (G)-allele has been positively selected during Chinese wheat breeding. Thus, these results can be used for further positional cloning and marker-assisted selection in wheat breeding programs. Seventeen stable QTLs related to kernel traits were identified. The stable QTLs for thousand kernel weight were mainly affected by kernel width. TaFT-D1 could be the candidate gene for QTLs QTkw.cas-7D.2 and QKw.cas-7D.1. 相似文献