Rice DNA-Binding One Zinc Finger 24 (OsDOF24) Delays Leaf Senescence in a Jasmonate-Mediated Pathway

Abstract Leaf senescence is the final stage of leaf development and in cereal crops, the timing of senescence relative to grain filling has major effects on agronomic traits such as yield. Although many genetic factors are involved in the regulation of leaf senescence in cereals, the key regulators remain to be determined. Plant transcription factors with a conserved DOF (DNA-binding one zinc finger) domain play roles in multiple physiological processes. Here, we show a novel function for OsDOF24 as a repressor of leaf senescence in rice (Oryza sativa). In wild-type leaves, OsDOF24 expression rapidly decreased during natural senescence (NS) and dark-induced senescence (DIS). The gain-of-function mutant osdof24-D, which contains an enhancer-trap T-DNA in the OsDOF24 promoter, exhibited delayed leaf yellowing during NS and DIS. Transgenic plants overexpressing OsDOF24 showed the same phenotype during DIS. Reverse-transcription quantitative real-time PCR analysis revealed that senescence-associated genes (Osl85, Osl57 and OsNAP) and chlorophyll degradation genes (NYC1, NYC3 and SGR) were downregulated in the osdof24-D mutant during dark incubation. Among the phytohormones, only methyl jasmonate induced OsDOF24 expression. Furthermore, the reduced expression of jasmonate biosynthesis-related genes (OsLOX2, OsLOX8, OsHI-LOX, OsAOS1 and OsAOS2) in osdof24-D decreased endogenous jasmonate levels, resulting in delayed leaf senescence under DIS conditions. Yeast one-hybrid assays showed that OsDOF24 binds to the promoter region of OsAOS1. Taken together, our results demonstrate that OsDOF24 suppresses the induction of leaf senescence during vegetative growth by deactivating jasmonate biosynthetic pathways.

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Mutation of ONAC096 Enhances Grain Yield by Increasing Panicle Number and Delaying Leaf Senescence during Grain Filling in Rice

International Journal of Molecular Sciences ◽

10.3390/ijms20205241 ◽

2019 ◽

Vol 20 (20) ◽

pp. 5241 ◽

Cited By ~ 6

Author(s):

Kiyoon Kang ◽

Yejin Shim ◽

Eunji Gi ◽

Gynheung An ◽

Nam-Chon Paek

Keyword(s):

Grain Yield ◽

Leaf Senescence ◽

Grain Filling ◽

Pcr Analysis ◽

Cytokinin Oxidase ◽

Panicle Number ◽

Reverse Transcription Quantitative Pcr ◽

Dna Insertion ◽

Upregulated Genes ◽

Insertion Mutants

Exploring genetic methods to improve yield in grain crops such as rice (Oryza sativa) is essential to help meet the needs of the increasing population. Here, we report that rice ONAC096 affects grain yield by regulating leaf senescence and panicle number. ONAC096 expression increased rapidly in rice leaves upon the initiation of aging- and dark-induced senescence. Two independent T-DNA insertion mutants (onac096-1 and onac096-2) with downregulated ONAC096 expression retained their green leaf color during natural senescence in the field, thus extending their photosynthetic capacity. Reverse-transcription quantitative PCR analysis showed that ONAC096 upregulated genes controlling chlorophyll degradation and leaf senescence. Repressed OsCKX2 (encoding cytokinin oxidase/dehydrogenase) expression in the onac096 mutants led to a 15% increase in panicle number without affecting grain weight or fertility. ONAC096 mediates abscisic acid (ABA)-induced leaf senescence by upregulating the ABA signaling genes ABA INSENSITIVE5 and ENHANCED EM LEVEL. The onac096 mutants showed a 16% increase in grain yield, highlighting the potential for using this gene to increase grain production.

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Faculty Opinions recommendation of Reduction in DNA-binding affinity of Cys2His2 zinc finger proteins by linker phosphorylation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1019055.215578 ◽

2004 ◽

Author(s):

Philip Dawson

Keyword(s):

Dna Binding ◽

Binding Affinity ◽

Zinc Finger ◽

Zinc Finger Proteins ◽

Dna Binding Affinity

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Faculty Opinions recommendation of Embryonic neural inducing factor churchill is not a DNA-binding zinc finger protein: solution structure reveals a solvent-exposed beta-sheet and zinc binuclear cluster.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1100091.556249 ◽

2008 ◽

Author(s):

Thomas Friedman

Keyword(s):

Dna Binding ◽

Zinc Finger ◽

Solution Structure ◽

Zinc Finger Protein ◽

Beta Sheet ◽

Protein Solution ◽

Binuclear Cluster ◽

Finger Protein ◽

Zinc Binuclear Cluster

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Effect of PASP-KT-NAA on Leaf Senescence and Grain Filling Rate during the Grain-Filling Period in Different Temperature Zones

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2012.01698 ◽

2013 ◽

Vol 38 (9) ◽

pp. 1698-1709

Author(s):

Tian-Jun XU ◽

Zhi-Qiang DONG ◽

Jiao GAO ◽

Chuan-Xiao CHEN ◽

Liu JIAO ◽

...

Keyword(s):

Leaf Senescence ◽

Grain Filling ◽

Filling Rate ◽

Grain Filling Rate ◽

Grain Filling Period

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Specific DNA binding to a major histocompatibility complex enhancer sequence by a synthetic 57-residue double zinc finger peptide from a human enhancer binding protein.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(20)89645-8 ◽

1991 ◽

Vol 266 (11) ◽

pp. 7306-7311

Author(s):

K Sakaguchi ◽

E Appella ◽

J G Omichinski ◽

G M Clore ◽

A M Gronenborn

Keyword(s):

Major Histocompatibility Complex ◽

Dna Binding ◽

Zinc Finger ◽

Binding Protein ◽

Major Histocompatibility ◽

Enhancer Sequence ◽

Histocompatibility Complex ◽

Enhancer Binding Protein ◽

Zinc Finger Peptide

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The apple C2H2-type zinc finger transcription factor MdZAT10 positively regulates JA-induced leaf senescence by interacting with MdBT2

Horticulture Research ◽

10.1038/s41438-021-00593-0 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Kuo Yang ◽

Jian-Ping An ◽

Chong-Yang Li ◽

Xue-Na Shen ◽

Ya-Jing Liu ◽

...

Keyword(s):

Mass Spectrometry ◽

Transcription Factor ◽

Liquid Chromatography ◽

Zinc Finger ◽

Leaf Senescence ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Liquid Chromatography Mass Spectrometry ◽

Zinc Finger Transcription Factor ◽

Insight Into

AbstractJasmonic acid (JA) plays an important role in regulating leaf senescence. However, the molecular mechanisms of leaf senescence in apple (Malus domestica) remain elusive. In this study, we found that MdZAT10, a C2H2-type zinc finger transcription factor (TF) in apple, markedly accelerates leaf senescence and increases the expression of senescence-related genes. To explore how MdZAT10 promotes leaf senescence, we carried out liquid chromatography/mass spectrometry screening. We found that MdABI5 physically interacts with MdZAT10. MdABI5, an important positive regulator of leaf senescence, significantly accelerated leaf senescence in apple. MdZAT10 was found to enhance the transcriptional activity of MdABI5 for MdNYC1 and MdNYE1, thus accelerating leaf senescence. In addition, we found that MdZAT10 expression was induced by methyl jasmonate (MeJA), which accelerated JA-induced leaf senescence. We also found that the JA-responsive protein MdBT2 directly interacts with MdZAT10 and reduces its protein stability through ubiquitination and degradation, thereby delaying MdZAT10-mediated leaf senescence. Taken together, our results provide new insight into the mechanisms by which MdZAT10 positively regulates JA-induced leaf senescence in apple.

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Advances in Cereal Crop Genomics for Resilience under Climate Change

Life ◽

10.3390/life11060502 ◽

2021 ◽

Vol 11 (6) ◽

pp. 502

Author(s):

Tinashe Zenda ◽

Songtao Liu ◽

Anyi Dong ◽

Huijun Duan

Keyword(s):

Climate Change ◽

Genome Sequencing ◽

Gene Editing ◽

Agronomic Traits ◽

Cereal Crops ◽

Agricultural System ◽

Plant Genomics ◽

Crop Species ◽

Underutilized Species ◽

Recent Developments

Adapting to climate change, providing sufficient human food and nutritional needs, and securing sufficient energy supplies will call for a radical transformation from the current conventional adaptation approaches to more broad-based and transformative alternatives. This entails diversifying the agricultural system and boosting productivity of major cereal crops through development of climate-resilient cultivars that can sustainably maintain higher yields under climate change conditions, expanding our focus to crop wild relatives, and better exploitation of underutilized crop species. This is facilitated by the recent developments in plant genomics, such as advances in genome sequencing, assembly, and annotation, as well as gene editing technologies, which have increased the availability of high-quality reference genomes for various model and non-model plant species. This has necessitated genomics-assisted breeding of crops, including underutilized species, consequently broadening genetic variation of the available germplasm; improving the discovery of novel alleles controlling important agronomic traits; and enhancing creation of new crop cultivars with improved tolerance to biotic and abiotic stresses and superior nutritive quality. Here, therefore, we summarize these recent developments in plant genomics and their application, with particular reference to cereal crops (including underutilized species). Particularly, we discuss genome sequencing approaches, quantitative trait loci (QTL) mapping and genome-wide association (GWAS) studies, directed mutagenesis, plant non-coding RNAs, precise gene editing technologies such as CRISPR-Cas9, and complementation of crop genotyping by crop phenotyping. We then conclude by providing an outlook that, as we step into the future, high-throughput phenotyping, pan-genomics, transposable elements analysis, and machine learning hold much promise for crop improvements related to climate resilience and nutritional superiority.

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Ear moisture during kernel development as influenced by field and laboratory selection

Canadian Journal of Plant Science ◽

10.4141/cjps95-097 ◽

1995 ◽

Vol 75 (3) ◽

pp. 557-563 ◽

Cited By ~ 2

Author(s):

H. Z. Cross

Keyword(s):

Moisture Content ◽

Field Study ◽

Agronomic Traits ◽

Grain Filling ◽

Kernel Weight ◽

Test Weight ◽

Mass Selection ◽

Dry Matter Accumulation ◽

Drying Characteristics ◽

Laboratory Selection

Grain quality, timeliness of harvest, and profitability can be increased by improving field drying characteristics of maize (Zea mays L.) hybrids. To better understand hows genes control ear drying, I compared maize strains developed by divergently selecting three cycles for (1) high HM or low LM moisture content at 45 d post pollination in the field or (2) fast FD vs. slow ear drying SD In laboratory. A field study across five locations compared HM, LM, FD, and SD strains from each of five synthetics for grain yield, ear moisture at harvest, test weight, lodging, and other agronomic traits. I studied ear moisture during grain filling for two subsets of divergently selected strains from one and three synthetics for 2 yr. In a third 2-yr field study, I measured mature kernel weight, lag period duration (LPD), effective grain-filling period (EFPD), and rate of dry matter accumulation (RDMA) for LM and HM strains developed from each of four synthetics. When averaged across the five synthetics, both SD and LM selections produced equivalent yields but lower ear moisture at harvest than the corresponding divergent strains. The LM strains had higher test weights than HM strains. When averaged across three synthetics and 2 yr, the HM strains produced higher moisture than LM strains at 15, 30, 45, and 60 d after silking. However, environments also influenced moisture content of the kernels during grain filling. In three of the four synthetics studied, HM strains had heavier kernels than corresponding LM strains. The heavier kernels seem to be due to increased RDMA. When averaged across four synthetics, LM strains had shorter LPD than HM strains. These correlated selection responses suggest that a genetic association exists among moisture content during grain filling, moisture content at physiological maturity, moisture content at harvest, LPD, and test weight. Breeding for LM or SD should improve field-drying characteristics of maize without increasing stalk breakage or decreasing yields. Key words:Zea mays L., grain filling, dry-down rates, mass selection, breeding methods

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The C6 zinc finger and adjacent amino acids determine DNA-binding specificity and affinity in the yeast activator proteins LAC9 and PPR1.

Molecular and Cellular Biology ◽

10.1128/mcb.10.10.5128 ◽

1990 ◽

Vol 10 (10) ◽

pp. 5128-5137 ◽

Cited By ~ 10

Author(s):

M M Witte ◽

R C Dickson

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Dna Binding ◽

Zinc Finger ◽

Binding Specificity ◽

Binding Domain ◽

Dna Binding Domain ◽

Transcription Activator ◽

Activator Proteins ◽

Dna Binding Specificity

LAC9 is a DNA-binding protein that regulates transcription of the lactose-galactose regulon in Kluyveromyces lactis. The DNA-binding domain is composed of a zinc finger and nearby amino acids (M. M. Witte and R. C. Dickson, Mol. Cell. Biol. 8:3726-3733, 1988). The single zinc finger appears to be structurally related to the zinc finger of many other fungal transcription activator proteins that contain positively charged residues and six conserved cysteines with the general form Cys-Xaa2-Cys-Xaa6-Cys-Xaa6-9-Cys-Xaa2-Cys-Xaa 6-Cys, where Xaan indicates a stretch of the indicated number of any amino acids (R. M. Evans and S. M. Hollenberg, Cell 52:1-3, 1988). The function(s) of the zinc finger and other amino acids in DNA-binding remains unclear. To determine which portion of the LAC9 DNA-binding domain mediates sequence recognition, we replaced the C6 zinc finger, amino acids adjacent to the carboxyl side of the zinc finger, or both with the analogous region from the Saccharomyces cerevisiae PPR1 or LEU3 protein. A chimeric LAC9 protein, LAC9(PPR1 34-61), carrying only the PPR1 zinc finger, retained the DNA-binding specificity of LAC9. However, LAC9(PPR1 34-75), carrying the PPR1 zinc finger and 14 amino acids on the carboxyl side of the zinc finger, gained the DNA-binding specificity of PPR1, indicating that these 14 amino acids are necessary for specific DNA binding. Our data show that C6 fingers can substitute for each other and allow DNA binding, but binding affinity is reduced. Thus, in a qualitative sense C6 fingers perform a similar function(s). However, the high-affinity binding required by natural C6 finger proteins demands a unique C6 finger with a specific amino acid sequence. This requirement may reflect conformational constraints, including interactions between the C6 finger and the carboxyl-adjacent amino acids; alternatively or in addition, it may indicate that unique, nonconserved amino acid residues in zinc fingers make sequence-specifying or stabilizing contacts with DNA.

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