Identification and Characterization of HAESA-Like Genes Involved in the Fruitlet Abscission in Litchi

Regulation of abscission is an important agricultural concern since precocious abscission can reduce crop yield. INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) peptide and its receptors the HAESA (HAE) and HAESA-like2 (HSL2) kinases have been revealed to be core components controlling floral organ abscission in the model plant Arabidopsis. However, it is still unclear whether the homologs of IDA-HAE/HSL2 in non-model plants are correlated to abscission. Previously, we found LcIDL1, a homolog of IDA from litchi, has a similar role to AtIDA in control of floral organ abscission in Arabidopsis. Here, we further isolated an HAESA-like homolog, LcHSL2, which is likely involved in the fruitlet abscission in litchi. Ectopic expression of LcHSL2 in wild type Arabidopsis has no effect on the floral organ abscission. However, its presence in the hae hsl2 mutant background completely rescued the floral organ abscission deficiency. LcHSL2 is localized in the cell membrane and the LcHSL2 gene is expressed at the pedicel abscission zone (AZ) of litchi and floral AZ of Arabidopsis. Real-time PCR analysis showed that the expression level of LcHSL2 was increased during ethephon-induced fruitlet abscission in litchi. Taken together, our findings suggest that HSL2 homologs have functional conservation in Arabidopsis and litchi, and LcHSL2 might play a critical role in regulation of fruitlet abscission in litchi.

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Characterization of Two Ethephon-Induced IDA-Like Genes from Mango, and Elucidation of Their Involvement in Regulating Organ Abscission

Genes ◽

10.3390/genes12030439 ◽

2021 ◽

Vol 12 (3) ◽

pp. 439

Author(s):

Avinash Chandra Rai ◽

Eyal Halon ◽

Hanita Zemach ◽

Tali Zviran ◽

Isaac Sisai ◽

...

Keyword(s):

Expression Profiles ◽

Mangifera Indica ◽

Ectopic Expression ◽

Fruit Trees ◽

Floral Organ ◽

Cytosolic Ph ◽

Early Increase ◽

Encoding Genes ◽

Fruitlet Abscission

In mango (Mangifera indica L.), fruitlet abscission limits productivity. The INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) peptide acts as a key component controlling abscission events in Arabidopsis. IDA-like peptides may assume similar roles in fruit trees. In this study, we isolated two mango IDA-like encoding-genes, MiIDA1 and MiIDA2. We used mango fruitlet-bearing explants and fruitlet-bearing trees, in which fruitlets abscission was induced using ethephon. We monitored the expression profiles of the two MiIDA-like genes in control and treated fruitlet abscission zones (AZs). In both systems, qRT-PCR showed that, within 24 h, both MiIDA-like genes were induced by ethephon, and that changes in their expression profiles were associated with upregulation of different ethylene signaling-related and cell-wall modifying genes. Furthermore, ectopic expression of both genes in Arabidopsis promoted floral-organ abscission, and was accompanied by an early increase in the cytosolic pH of floral AZ cells—a phenomenon known to be linked with abscission, and by activation of cell separation in vestigial AZs. Finally, overexpression of both genes in an Atida mutant restored its abscission ability. Our results suggest roles for MiIDA1 and MiIDA2 in affecting mango fruitlet abscission. Based on our results, we propose new possible modes of action for IDA-like proteins in regulating organ abscission.

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Functional Characterization of BRASSINAZOLE-RESISTANT 1 in Panax Ginseng (PgBZR1) and Brassinosteroid Response during Storage Root Formation

International Journal of Molecular Sciences ◽

10.3390/ijms21249666 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9666

Author(s):

Hyeona Hwang ◽

Hwa-Yong Lee ◽

Hojin Ryu ◽

Hyunwoo Cho

Keyword(s):

Panax Ginseng ◽

Glycogen Synthase ◽

Functional Characterization ◽

Secondary Growth ◽

Ectopic Expression ◽

Floral Organ ◽

Membrane Receptors ◽

Storage Root ◽

Functional Conservation

Brassinosteroids (BRs) play crucial roles in the physiology and development of plants. In the model plant Arabidopsis, BR signaling is initiated at the level of membrane receptors, BRASSINOSTEROIDS INSENSITIVE 1 (BRI1) and BRI1-ASSOCIATED RECEPTOR KINASE 1 (BAK1) complex, thus activating the transcription factors (TFs) BRASSINAZOLE RESISTANT 1/BRI1-EMS-SUPPRESSOR 1 (BZR1/BES1) to coordinate BR responsive genes. BRASSINOSTEROIDS INSENSITIVE 2 (BIN2), glycogen synthase kinase 3 (GSK3) like-kinase, negatively regulates BZR1/BES1 transcriptional activity through phosphorylation-dependent cytosolic retention and shuttling. However, it is still unknown whether this mechanism is conserved in Panax ginseng C. A. Mayer, a member of the Araliaceae family, which is a shade-tolerant perennial root crop. Despite its pharmacological and agricultural importance, the role of BR signaling in the development of P. ginseng and characterization of BR signaling components are still elusive. In this study, by utilizing the Arabidopsisbri1 mutant, we found that ectopic expression of the gain of function form of PgBZR1 (Pgbzr1-1D) restores BR deficiency. In detail, ectopic expression of Pgbzr1-1D rescues dwarfism, defects of floral organ development, and hypocotyl elongation of bri1-5, implying the functional conservation of PgBZR1 in P. ginseng. Interestingly, brassinolide (BL) and BRs biosynthesis inhibitor treatment in two-year-old P. ginseng storage root interferes with and promotes, respectively, secondary growth in terms of xylem formation. Altogether, our results provide new insight into the functional conservation and potential diversification of BR signaling and response in P. ginseng.

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A Mutation in CsHY2 Encoding a Phytochromobilin (PΦB) Synthase Leads to an Elongated Hypocotyl 1(elh1) Phenotype in Cucumber (Cucumis sativus L.)

10.21203/rs.3.rs-182705/v1 ◽

2021 ◽

Author(s):

Liangliang Hu ◽

Peng Liu ◽

Zhuoshuai Jin ◽

Jing Sun ◽

Yiqun Weng ◽

...

Keyword(s):

Cell Elongation ◽

Ectopic Expression ◽

Rna Seq ◽

Wild Type ◽

Hypocotyl Growth ◽

Hypocotyl Length ◽

Critical Determinant ◽

Cucumis Sativus L ◽

Identification And Characterization

Abstract Hypocotyl length is a critical determinant in establishing high quality seedlings for successful cucumber production, but knowledge on the molecular regulation of hypocotyl growth in cucumber is very limited. Here we reported identification and characterization of a cucumber elongated hypocotyl 1 (elh1) mutant. We found that the longer hypocotyl in elh1 was due to longitudinal growth of hypocotyl cells. With fine mapping, the elh1 locus was delimited to a 20.9-kb region containing three annotated genes; only one polymorphism was identified in this region between two parental lines, which was a non-synonymous SNP (G28153633A) in the third exon of CsHY2 (CsGy1G030000) that encodes a phytochromobilin (PΦB) synthase. Uniqueness of the mutant allele at CsHY2 was verified in 515 cucumber lines. Ectopic expression of CsHY2 in Arabidopsis hy2-1 mutant led to reduced hypocotyl length. The PΦB protein was targeted to chloroplasts. The expression levels of CsHY2 and five phytochrome genes, CsPHYA1, CsPHYA2, CsPHYB, CsPHYC and CsPHYE were all significantly down-regulated while several cell elongation related genes were up-regulated in elh1 mutant compared to wild type cucumber, which are correlated with dynamic hypocotyl elongation in the mutant. RNA-seq analysis in the WT and mutant revealed differentially expressed genes involved in porphyrin and chlorophyll metabolisms, cell elongation, and plant hormone signal transduction pathways. This is the first report to characterize and clone the CsHY2 gene in cucumber. This work reveals the important of CsHY2 in regulating hypocotyl length and extends our understanding of the roles of CsHY2 in cucumber.

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Genome-Wide Identification and Characterization of Hsf and Hsp Gene Families and Gene Expression Analysis under Heat Stress in Eggplant (Solanum melongema L.)

Horticulturae ◽

10.3390/horticulturae7060149 ◽

2021 ◽

Vol 7 (6) ◽

pp. 149

Author(s):

Chao Gong ◽

Qiangqiang Pang ◽

Zhiliang Li ◽

Zhenxing Li ◽

Riyuan Chen ◽

...

Keyword(s):

Heat Stress ◽

Gene Families ◽

High Temperature Stress ◽

Pcr Analysis ◽

Rna Seq ◽

Genome Wide ◽

Motif Composition ◽

Hsp Genes ◽

Identification And Characterization

Under high temperature stress, a large number of proteins in plant cells will be denatured and inactivated. Meanwhile Hsfs and Hsps will be quickly induced to remove denatured proteins, so as to avoid programmed cell death, thus enhancing the thermotolerance of plants. Here, a comprehensive identification and analysis of the Hsf and Hsp gene families in eggplant under heat stress was performed. A total of 24 Hsf-like genes and 117 Hsp-like genes were identified from the eggplant genome using the interolog from Arabidopsis. The gene structure and motif composition of Hsf and Hsp genes were relatively conserved in each subfamily in eggplant. RNA-seq data and qRT-PCR analysis showed that the expressions of most eggplant Hsf and Hsp genes were increased upon exposure to heat stress, especially in thermotolerant line. The comprehensive analysis indicated that different sets of SmHsps genes were involved downstream of particular SmHsfs genes. These results provided a basis for revealing the roles of SmHsps and SmHsp for thermotolerance in eggplant, which may potentially be useful for understanding the thermotolerance mechanism involving SmHsps and SmHsp in eggplant.

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Characterization of Plasmodium falciparum NEDD8 and identification of cullins as its substrates

10.1101/2020.07.21.213488 ◽

2020 ◽

Author(s):

Manish Bhattacharjee ◽

Navin Adhikari ◽

Renu Sudhakar ◽

Zeba Rizvi ◽

Divya Das ◽

...

Keyword(s):

Mass Spectrometry ◽

Plasmodium Falciparum ◽

Western Blot ◽

Wild Type ◽

Malaria Parasites ◽

Post Translational Modifications ◽

Functional Conservation ◽

Cellular Processes ◽

Physiological Substrates

ABSTRACTA variety of post-translational modifications of Plasmodium falciparum proteins, including phosphorylation and ubiquitination, are shown to have key regulatory roles. The neural precursor cell expressed developmentally downregulated protein 8 (NEDD8) is a ubiquitin-like modifier of cullin-RING E3 ubiquitin ligases, which regulate diverse cellular processes, including the cell-cycle. Although neddylation pathway is conserved in eukaryotes, it is yet to be characterized in Plasmodium and related apicomplexan parasites. Towards studying the neddylation pathway in malaria parasites, we characterized P. falciparum NEDD8 (PfNEDD8) and identified cullins as its physiological substrates. PfNEDD8 is a 76 amino acid residue protein without the C-terminal tail, indicating that it can be readily conjugated. The wild type and mutant (Gly75Gly76 mutated to Ala75Ala76) PfNEDD8 were expressed in P. falciparum. Western blot of wild type PfNEDD8-expressing parasites indicated multiple high molecular weight conjugates, which were absent in the parasites expressing the mutant, indicating conjugation of NEDD8 to proteins through Gly76. Immunoprecipitation followed by mass spectrometry of wild type PfNEDD8-expressing parasites identified several proteins, including two putative cullins. Furthermore, we expressed PfNEDD8 in mutant S. cerevisiae strains that lacked endogenous NEDD8 (Δrub1) or NEDD8 conjugating E2 enzyme (ΔUbc12). The western blot of complemented strains and mass spectrometry of PfNEDD8 immunoprecipitate showed conjugation of PfNEDD8 to S. cerevisiae cullin cdc53, demonstrating functional conservation and cullins as the physiological substrates of PfNEDD8. The characterization of PfNEDD8 and identification of cullins as its substrates make ground for investigation of specific roles and drug target potential of neddylation pathway in malaria parasites.

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Identification and Characterization of the Phage Gene sav, Involved in Sensitivity to the Lactococcal Abortive Infection Mechanism AbiV

Applied and Environmental Microbiology ◽

10.1128/aem.02093-08 ◽

2009 ◽

Vol 75 (8) ◽

pp. 2484-2494 ◽

Cited By ~ 17

Author(s):

Jakob Haaber ◽

Geneviève M. Rousseau ◽

Karin Hammer ◽

Sylvain Moineau

Keyword(s):

Gel Filtration ◽

Point Mutations ◽

Whole Genome ◽

Wild Type ◽

Abortive Infection ◽

Native Form ◽

Phage Gene ◽

Infection Mechanism ◽

Identification And Characterization

ABSTRACT Lactococcus lactis phage mutants that are insensitive to the recently characterized abortive infection mechanism AbiV were isolated and analyzed in an effort to elucidate factors involved in the sensitivity to AbiV. Whole-genome sequencing of the phage mutants p2.1 and p2.2 revealed mutations in an orf that is transcribed early, indicating that this orf was responsible for AbiV sensitivity. Sequencing of the homologous regions in the genomes of other AbiV-insensitive mutants derived from p2 and six other lactococcal wild-type phages revealed point mutations in the homologous orf sequences. The orf was named sav (for sensitivity to AbiV), and the encoded polypeptide was named SaV. The purification of a His-tagged SaV polypeptide by gel filtration suggested that the polypeptide formed a dimer in its native form. The overexpression of SaV in L. lactis and Escherichia coli led to a rapid toxic effect. Conserved, evolutionarily related regions in SaV polypeptides of different phage groups are likely to be responsible for the AbiV-sensitive phenotype and the toxicity.

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The identification and characterization of a testis-specific cDNA during spermatogenesis

Cellular & Molecular Biology Letters ◽

10.2478/s11658-006-0008-4 ◽

2006 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Ying Chen ◽

Jiarui Hu ◽

Ping Song ◽

Wuming Gong

Keyword(s):

Experimental Validation ◽

Rna Binding ◽

Pcr Analysis ◽

Splicing Factors ◽

Rt Pcr ◽

Rich Domain ◽

Pachytene Spermatocytes ◽

Identification And Characterization

AbstractUsing bioinformatics and experimental validation, we obtained a cDNA (named srsf) which was exclusively expressed in the mouse testes. RT-PCR analysis showed that srsf mRNA was not expressed in the gonad during the sex determination period or during embryogenesis. In developing mouse tests, srsf expression was first detected on post-natal day 10, reached its highest level on day 23, and then reduced to and remained at a moderate level throughout adulthood. In situ hybridization analysis demonstrated that srsf mRNA was expressed in pachytene spermatocytes and round spermatids in the testes. The predicted protein contains one RNA-binding domain (RBD) and a serine-arginine rich domain (RS), which are characterized by some splicing factors of SR family members. These findings indicate that srsf may play a role during spermatogenesis.

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A Ral GAP complex links PI 3-kinase/Akt signaling to RalA activation in insulin action

Molecular Biology of the Cell ◽

10.1091/mbc.e10-08-0665 ◽

2011 ◽

Vol 22 (1) ◽

pp. 141-152 ◽

Cited By ~ 65

Author(s):

Xiao-Wei Chen ◽

Dara Leto ◽

Tingting Xiong ◽

Genggeng Yu ◽

Alan Cheng ◽

...

Keyword(s):

Glucose Transporter ◽

Critical Role ◽

Inhibitory Effect ◽

Small Gtpase ◽

Regulatory Subunit ◽

Hydrolysis Of ◽

Identification And Characterization

Insulin stimulates glucose transport in muscle and adipose tissue by translocation of glucose transporter 4 (GLUT4) to the plasma membrane. We previously reported that activation of the small GTPase RalA downstream of PI 3-kinase plays a critical role in this process by mobilizing the exocyst complex for GLUT4 vesicle targeting in adipocytes. Here we report the identification and characterization of a Ral GAP complex (RGC) that mediates the activation of RalA downstream of the PI 3-kinase/Akt pathway. The complex is composed of an RGC1 regulatory subunit and an RGC2 catalytic subunit (previously identified as AS250) that directly stimulates the guanosine triphosphate hydrolysis of RalA. Knockdown of RGC proteins leads to increased RalA activity and glucose uptake in adipocytes. Insulin inhibits the GAP complex through Akt2-catalyzed phosphorylation of RGC2 in vitro and in vivo, while activated Akt relieves the inhibitory effect of RGC proteins on RalA activity. The RGC complex thus connects PI 3-kinase/Akt activity to the transport machineries responsible for GLUT4 translocation.

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Transferrin-a modulates hepcidin expression in zebrafish embryos

Blood ◽

10.1182/blood-2008-06-165340 ◽

2009 ◽

Vol 113 (12) ◽

pp. 2843-2850 ◽

Cited By ~ 36

Author(s):

Paula G. Fraenkel ◽

Yann Gibert ◽

Jason L. Holzheimer ◽

Victoria J. Lattanzi ◽

Sarah F. Burnett ◽

...

Keyword(s):

Large Scale ◽

Critical Role ◽

Hypochromic Anemia ◽

Zebrafish Embryos ◽

Genetic Screens ◽

Hepcidin Expression ◽

Morpholino Knockdown ◽

Low Levels ◽

Identification And Characterization

Abstract The iron regulatory hormone hepcidin is transcriptionally up-regulated in response to iron loading, but the mechanisms by which iron levels are sensed are not well understood. Large-scale genetic screens in the zebrafish have resulted in the identification of hypochromic anemia mutants with a range of mutations affecting conserved pathways in iron metabolism and heme synthesis. We hypothesized that transferrin plays a critical role both in iron transport and in regulating hepcidin expression in zebrafish embryos. Here we report the identification and characterization of the zebrafish hypochromic anemia mutant, gavi, which exhibits transferrin deficiency due to mutations in transferrin-a. Morpholino knockdown of transferrin-a in wild-type embryos reproduced the anemia phenotype and decreased somite and terminal gut iron staining, while coinjection of transferrin-a cRNA partially restored these defects. Embryos with transferrin-a or transferrin receptor 2 (TfR2) deficiency exhibited low levels of hepcidin expression, however anemia, in the absence of a defect in the transferrin pathway, failed to impair hepcidin expression. These data indicate that transferrin-a transports iron and that hepcidin expression is regulated by a transferrin-a–dependent pathway in the zebrafish embryo.

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Identification and Characterization of a New Lipoprotein, NlpI, in Escherichia coli K-12

Journal of Bacteriology ◽

10.1128/jb.181.14.4318-4325.1999 ◽

1999 ◽

Vol 181 (14) ◽

pp. 4318-4325 ◽

Cited By ~ 42

Author(s):

Masaru Ohara ◽

Henry C. Wu ◽

Krishnan Sankaran ◽

Paul D. Rick

Keyword(s):

Escherichia Coli ◽

Direct Consequence ◽

Insertion Mutant ◽

Polynucleotide Phosphorylase ◽

Wild Type ◽

E Coli ◽

K 12 ◽

Identification And Characterization ◽

Lines Of Evidence

ABSTRACT We report here the identification of a new lipoprotein, NlpI, inEscherichia coli K-12. The NlpI structural gene (nlpI) is located between the genes pnp(polynucleotide phosphorylase) and deaD (RNA helicase) at 71 min on the E. coli chromosome. The nlpI gene encodes a putative polypeptide of approximately 34 kDa, and multiple lines of evidence clearly demonstrate that NlpI is indeed a lipoprotein. An nlpI::cm mutation rendered growth of the cells osmotically sensitive, and incubation of the insertion mutant at an elevated temperature resulted in the formation of filaments. The altered phenotype of the mutant was a direct consequence of the mutation in nlpI, since it was complemented by the wild-type nlpI gene alone. Overexpression of the unaltered nlpI gene in wild-type cells resulted in the loss of the rod morphology and the formation of single prolate ellipsoids and pairs of prolate ellipsoids joined by partial constrictions. NlpI may be important for an as-yet-undefined step in the overall process of cell division.

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