Papers by Jeanmarie Verchot
Springer eBooks, 2011
ABSTRACT VirionPotato virus X. Fig. 1Length of bar (nm): 340 (Extracted from Virology (1992) 191:... more ABSTRACT VirionPotato virus X. Fig. 1Length of bar (nm): 340 (Extracted from Virology (1992) 191:223–230. With permission from Academic Press, USA)GenomeReplicationHistoryGenus MembersGenome organization of potexviruses. Fig. 2Boxes represent open reading frames and the numbers the approximate size (kDa) of the encoded proteins; the 5′ cap (m7G) and 3′ poly A tail (AAAA) are shown; open reading frames for MPa, MPb, and MPc overlap (triple gene block)Nucleotide SequencesProteinsBiologyDiseasesVector ConstructsFig. 3
Southwestern Entomologist, Jun 1, 2003
... J Verchot, GW Horn, EG Krenzer, TF Peeper, ME Payton, GJ Michels, JB Bible, DA Owings ... sec... more ... J Verchot, GW Horn, EG Krenzer, TF Peeper, ME Payton, GJ Michels, JB Bible, DA Owings ... secalinus L.), and on grain yield and yield components were determined during crop years 1999-2000 ... aphid abundance (as much as 87%) and BYDV levels (as much as 70%), but often ...
Molecular Plant Pathology, Nov 17, 2021
TaxonomyPotato virus X is the type‐member of the plant‐infecting Potexvirus genus in the family A... more TaxonomyPotato virus X is the type‐member of the plant‐infecting Potexvirus genus in the family Alphaflexiviridae.Physical propertiesPotato virus X (PVX) virions are flexuous filaments 460–480 nm in length. Virions are 13 nm in diameter and have a helical pitch of 3.4 nm. The genome is approximately 6.4 kb with a 5′ cap and 3′ poly(A) terminus. PVX contains five open reading frames, four of which are essential for cell‐to‐cell and systemic movement. One protein encodes the viral replicase. Cellular inclusions, known as X‐bodies, occur near the nucleus of virus‐infected cells.HostsThe primary host is potato, but it infects a wide range of dicots. Diagnostic hosts include Datura stramonium and Nicotiana tabacum. PVX is transmitted in nature by mechanical contact.Useful website https://talk.ictvonline.org/ictv‐reports/ictv_online_report/positive‐sense‐rna‐viruses/w/alphaflexiviridae/1330/genus‐potexvirus
Scientific Reports, Jul 9, 2020
The endoplasmic reticulum (ER) immunoglobulin binding proteins (BiPs) are molecular chaperones in... more The endoplasmic reticulum (ER) immunoglobulin binding proteins (BiPs) are molecular chaperones involved in normal protein maturation and refolding malformed proteins through the unfolded protein response (UPR). Plant BiPs belong to a multi-gene family contributing to development, immunity, and responses to environmental stresses. This study identified three BiP homologs in the Solanum tuberosum (potato) genome using phylogenetic, amino acid sequence, 3-D protein modeling, and gene structure analysis. These analyses revealed that StBiP1 and StBiP2 grouped with AtBiP2, whereas StBiP3 grouped with AtBiP3. While the protein sequences and folding structures are highly similar, these StBiPs are distinguishable by their expression patterns in different tissues and in response to environmental stressors such as treatment with heat, chemicals, or virus elicitors of UPR. Ab initio promoter analysis revealed that potato and Arabidopsis BiP1 and BiP2 promoters were highly enriched with cis-regulatory elements (CREs) linked to developmental processes, whereas BiP3 promoters were enriched with stress related CREs. The frequency and linear distribution of these CREs produced two phylogenetic branches that further resolve the groups identified through gene phylogeny and exon/ intron phase analysis. These data reveal that the CRE architecture of BiP promoters potentially define their spatio-temporal expression patterns under developmental and stress related cues. One of the best characterized molecular chaperones in the endoplasmic reticulum (ER) is the ER binding immunoglobulin protein (BiP), also known as the glucose receptor protein 78 (GRP78), is conserved across evolutionary kingdoms. BiP guides the co-translational translocation of nascent proteins into the ER, and chaperones protein folding and maturation. BiP contains N-terminal nucleotide-binding domain (NBD) and C-terminal substrate-binding domain (SBD). The NBD has two lobes surrounding the allosteric ATP-binding site to modulate substrate binding. The SBD has SBDβ and SBDα subdomains to bind the hydrophobic surfaces of newly translated proteins to prevent aggregation. The SBDβ is a pocket with two primary loops that surround the nascent polypeptide and, the SBDα lid is covering this pocket 1 . All BiP proteins have a C-terminal HDEL or KDEL signaling motif for ER retention 2 . Across eukaryotes, BiPs contribute to the unfolded protein response (UPR). Under normal condition, the mammalian BiP binds to and inhibits three ER stress sensors, protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring enzyme 1α (IRE1α) . BiP releases the sensors to activate ER-to-nucleus signaling cascades. BiP plays another key role in protein quality control by identifying and refolding misfolded proteins. The yeast Kar2p (BiP orthologue) binds to and inhibits the IRE1p, which is the master regulator of UPR. Dissociation of Kar2p/BiP releases the IRE1p/IRE1α to oligomerize and then splice the mRNA controlling production of the Hac1/XBP1 transcription factor 5 . In Arabidopsis, the ER stress sensors
Molecular Plant-microbe Interactions, Oct 1, 2010
Several RNA virus genera belonging to the Virgaviridae and Flexiviridae families encode proteins ... more Several RNA virus genera belonging to the Virgaviridae and Flexiviridae families encode proteins organized in a triple gene block (TGB) that facilitate cell-to-cell and longdistance movement. The TGB proteins have been traditionally classified as hordei-like or potex-like based on phylogenetic comparisons and differences in movement mechanisms of the Hordeivirus and Potexvirus spp. However, accumulating data from other model viruses suggests that a revised framework is needed to accommodate the profound differences in protein interactions occurring during infection and ancillary capsid protein requirements for movement. The goal of this article is to highlight common features of the TGB proteins and salient differences in movement properties exhibited by individual viruses encoding these proteins. We discuss common and divergent aspects of the TGB transport machinery, describe putative nucleoprotein movement complexes, highlight recent data on TGB protein interactions and topological properties, and review membrane associations occurring during subcellular targeting and cell-to-cell movement. We conclude that the existing models cannot be used to explain all TGB viruses, and we propose provisional Potexvirus, Hordeivirus, and Pomovirus models. We also suggest areas that might profit from future research on viruses harboring this intriguing arrangement of movement proteins.
Molecular Plant Pathology, Aug 29, 2019
Molecular Plant-microbe Interactions, Apr 1, 2005
In the last five years, we have gained significant insight into the role of the Potexvirus protei... more In the last five years, we have gained significant insight into the role of the Potexvirus proteins in virus movement and RNA silencing. Potexviruses require three movement proteins, named triple gene block (TGB)p1, TGBp2, and TGBp3, and the viral coat protein (CP) to facilitate viral cell-to-cell and vascular transport. TGBp1 is a multifunctional protein that has RNA helicase activity, promotes translation of viral RNAs, increases plasmodesmal size exclusion limits, and suppresses RNA silencing. TGBp2 and TGBp3 are membrane-binding proteins. CP is required for genome encapsidation and forms ribonucleoprotein complexes along with TGBp1 and viral RNA. This review considers the functions of the TGB proteins, how they interact with each other and CP, and how silencing suppression might be linked to viral transport. A new model of the mechanism for Potexvirus transport is proposed.
Elsevier eBooks, 2008
Dicer, or Dicer-like (DCL) enzymes RNAse III or RNAse-III-like enzymes responsible for digesting ... more Dicer, or Dicer-like (DCL) enzymes RNAse III or RNAse-III-like enzymes responsible for digesting the noncoding regions of mRNAs to produce 21-24 nt single-strand RNAs known as miRNAs and siRNAs. Green fluorescent protein (GFP) This is derived from jellyfish and fluorescence green. Excitation wavelength is 488 nm and emission is above 520 nm. Fusions involving GFP are often used to study protein subcellular targeting or distribution in tissues. MicroRNAs (miRNAs) Single-strand RNAs that are 21-24 nt in length are found in eukaryotes and arise from noncoding regions of transcripts. These are produced by nucleolytic processing by DICER, and RNAse-III-like enzyme. These are crucial components of the RNAi pathway. RNA interference (RNAi) Similar to posttranscriptional gene silencing. More specifically, cellular or synthetic small RNA molecules can target homologous mRNA for degradation thereby preventing gene expression. RNA silencing or post-transcriptional gene silencing (PTGS) Mechanism regulating gene expression by regulating RNA accumulation after transcription. Mechanism involves RNA degradation machinery to shut off gene expression. Short interfering RNAs (siRNAs) Double-strand RNAs that are 21-24 nt in length which are generated by DICER or Dicer-like enzymes. SiRNAs can spread systemically in C. elegans and may cause silencing in distal organs. Some single-strand RNAs are made double-strand by RNA-dependent RNA polymerases. These double-stranded products are then cleaved by DICER. Transcriptional gene silencing (TGS) Silencing of genes in the nucleus. A small RNA molecule triggers de novo DNA methylation thereby blocking transcription. Small RNA typically is homologous to the target gene. Virus-induced gene silencing (VIGS) Viral RNAs can trigger for PTGS similar to small RNAs. Several plant viruses have been engineered as vectors for use in experiments shutting off gene expression by PTGS. Fragments of genes, antisense RNAs, small RNAs can be introduced into the viral vector and silencing is induced upon inoculation with the recombinant virus.
Crop Science, May 1, 2003
Crop Science, Jul 1, 2004
Registration of 'Ok102' Wheat and 2002. Across seven environments, fall forage production 'Ok102'... more Registration of 'Ok102' Wheat and 2002. Across seven environments, fall forage production 'Ok102' (Reg. no. CV-941, PI 632635) is a hard red winter (measured by hand clipping at the soil surface in December, wheat (Triticum aestivum L.) developed cooperatively by the Feekes stages 2-4) averaged 2610 kg ha Ϫ1 for Ok102, com-Oklahoma Agric. Exp. Stn. and the USDA-ARS. Ok102 was pared with 2710 kg ha Ϫ1 for Ok101, 2790 kg ha Ϫ1 for 2174, released in March 2002, primarily on the basis of its resistance and 2770 kg ha Ϫ1 for Jagger. Across 40 site-years representing to several foliar diseases, excellent milling quality, and desirmostly grain-only trials, grain yield of these four cultivars were able dough strength for leavened bread products. 3000 kg ha Ϫ1 (Ok102), 2990 kg ha Ϫ1 (Ok101), 2920 kg ha Ϫ1 Ok102 was derived from the cross '2174'/'Cimarron' (PI (2174), and 3020 kg ha Ϫ1 (Jagger). From the same trials, grain 536993), performed in 1991. 2174 has the pedigree IL71-5662/ volume weight averaged 763 kg m Ϫ3 (Ok102), 746 kg m Ϫ3 'PL145' (PI 600840)//'2165' and was released by the Oklahoma (Ok101), 768 kg m Ϫ3 (2174), and 748 kg m Ϫ3 (Jagger). Agric. Exp. Stn. in 1997. Cimarron has the pedigree 'Payne' In greenhouse tests, juvenile plants of Ok102 exhibited a (CItr 17717)*2/CO725052 and was released by the Oklahoma susceptible reaction to leaf rust comprised of bulk samples of Agric. Exp. Stn. in 1990. Ok102 traces to the bulk progeny of urediniospores collected from wheat fields in Oklahoma in a single F 3:4 head row harvested in 1995. The F 2 and F 3 generaspring 1999 and 2000. From 1999 to 2002, Ok102 has consistions were evaluated and harvested as bulk populations in tently shown a resistant reaction to leaf rust in field trials Stillwater, OK. The head row progeny was selected in 1996 conducted in Texas and Oklahoma, having an approximate from a non-replicated nursery at Lahoma, OK, for its acceptrating of 1 (resistant) on a 1 (resistant)-to-9 (susceptible) scale. able winterhardiness, plant and head type, heading and matu-Hence, Ok102 has adult-plant resistance to wheat leaf rust rity date, leaf rust (caused by Puccinia triticina Eriks.) resisraces currently present in Oklahoma. On the basis of seedling tance, lodging resistance, grain yield, volume weight, kernel tests conducted by the USDA-ARS Cereal Disease Laboraplumpness, and mixograph properties. Subsequent generatory, St. Paul, MN, Ok102 is postulated to have Lr3 and Lr24. tions were advanced by bulk selfing in the field, with roguing Their tests also indicate that seedlings of Ok102 are susceptible of taller variants each year until 2002. Ok102 was evaluated or have an intermediate level of resistance to five (2001 tests) as OK97508 in replicated Oklahoma performance trials from to seven (2000 tests) races of stem rust [caused by Puccinia 1997 to 2001, and in the Southern Regional Performance Nursgraminis f. sp. tritici (Pers.:Pers.)], and are moderately susceptiery (SRPN) in 2000 and 2001. ble or susceptible to stem rust in the field. Results from field Ok102 is semidwarf but shorter than most HRW wheat trials in Oklahoma and Kansas indicate Ok102 is resistant to cultivars currently in production. Its mature-plant height Wheat soilborne mosaic virus (1 on a 1-to-9 scale). Ok102 (77 cm) is 8 cm shorter than 2174 and 'Ok101' (Carver et al., exhibits an intermediate reaction to Barley yellow dwarf virus 2003) and 7 cm shorter than 'Jagger' (Sears et al., 1997). in the field, similar to the reaction of one of its parents, 2174. Lodging resistance on a scale of 1 (highest) to 5 (lowest) is On the basis of seedling responses in the greenhouse to popuabout 2 for Ok102, compared with values of 1 for 2174, 3 for lations prevalent in Oklahoma, Ok102 is moderately resistant Ok101, and 4 for Jagger. Ok102 shows an intermediate reacto tan spot [caused by Pyrenophera tritici-repentis (Died.) tion to acidic, aluminum-toxic soil. With a tolerance rating of Drechs.] and resistant to powdery mildew [caused by Blumeria 3.2 on a scale of 1 (most tolerant) to 5 (most susceptible), graminis (DC.) E.O. Speer f. sp. tritici Em. Marchal]. Ok102 Ok102 is more sensitive to Al toxicity than Ok101 (1.3) and produces a heterogeneous response to the Great Plains bio-Jagger (1.6), but similar to 2174 (3.0). Ok102 breaks winter type of Hessian fly (Mayetiola destructor Say) and is susceptidormancy relatively late, but its heading date (123 d) is interble to Russian wheat aphid (Diuraphia noxia Mordvilko) and mediate among current cultivars. Comparative placement of to greenbug (Schizaphis graminum Rondani). cultivars for date of first-hollow-stem stage is Jagger Ͻ The fall growth habit of Ok102 is semierect, which is similar Ok101 Ͻ 2174 and Ok102. Precise differences are highly yearto 2174 but more erect than Ok101 and Jagger. Flag leaves dependent. Heading date of Ok102 is 2 d later than Ok101 of Ok102 at the boot stage are blue-green, erect, and twisted. and Jagger, the same as 2174, and 2 d earlier than '2137'. Spikes are white-chaffed, awned, tapering, middense, and in-This phenological pattern makes Ok102 well suited for winter clined to nodding (in approximately horizontal position) at grazing and grain production in a dual-purpose (graze-plusharvest-maturity. Kernels are red, hard textured, ovate to elgrain) management system. Another characteristic that lends liptical, and midlong, and they have a midwide, middeep Ok102 to dual-purpose production is coleoptile elongation, crease, rounded cheeks, and midsized germ. or the ability to emerge from deeper seed placement. When On the basis of single-kernel characterization system measured at 15ЊC in a growth chamber, coleoptile length of (SKCS) data recorded from 16 breeder trials from 1999 to Ok102 (8.7 cm) is 2.1 cm longer than Ok101 (short coleoptile), 2001, means and standard deviations for Ok102 were 29.6 and 0.4 cm longer than 2174 (moderately long), and 0.4 cm shorter 7.7 mg for kernel weight, 2.4 and 0.4 mm for kernel diameter, than Jagger (moderately long). Ok102 has a relatively high and 76 and 16 for kernel hardness. Values for 2174 were 29.6 seed dormancy rating based on germination tests conducted and 7.4 mg for kernel weight, 2.4 and 0.4 mm for kernel at 4 to 12 wk post-harvest for seed stored at ambient temperadiameter, and 75 and 16 for kernel hardness index. Hence, ture and germinated at 24/35ЊC night/day temperature. Seed physical quality attributes of Ok102 and 2174 are indistinguishdormancy is not expressed at 13ЊC constant storage temperaable on the basis of SKCS parameters. From 28 site-years in the ture. This rating is consistent with the high seed dormancy 2001 and 2002 Oklahoma wheat variety trials, wheat protein ratings for both parents of Ok102 (2174 and Cimarron). content of Ok102 (135 g kg Ϫ1) equaled that of 2174 and Jagger. Ok102 has greater dough strength than 2174 on the basis of Forage yield, grain yield, and grain volume weight were 1468 Reproduced from Crop Science. Published by Crop Science Society of America. All copyrights reserved.
PLOS Genetics, Apr 15, 2015
PLOS Genetics, Apr 15, 2015
<p><b>(A)</b> to <b>(C)</b> The untransformed or transformed CRY1 &... more <p><b>(A)</b> to <b>(C)</b> The untransformed or transformed CRY1 <i>Δhac1</i>::TRP cells, which were grown in the raffinose-containing medium for 8 h, were switched to galactose- or raffinose-containing medium for culture from OD<sub>600</sub> = 0.3. <b>(A)</b> After 10 h culture in the presence of raffinose, the cells were normalized to an OD<sub>600</sub> = 1.0 and 5-fold serial dilutions were spotted on raffinose-containing plates. The plates were kept at 30°C for 48 h. <b>(B)</b> and <b>(C)</b> Quantitative measurement of the effects of constitutive expression of HAC1p and bZIP60 on yeast growth in the presence of raffinose <b>(B)</b> and galactose <b>(C)</b>. After 5 and 10 h culture, the yeast cell density was determined by measuring the OD<sub>600</sub> (1 OD<sub>600</sub> = 5e+8). Note that the expression of <i>bZIP60</i> S and <i>bZIP60ΔN</i> S, not <i>bZIP60</i> U or <i>bZIP60ΔN</i> U, inhibits yeast growth, whereas the induction of both <i>HAC1</i> U and <i>HAC1</i> S leads to retarded growth (see <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1005164#pgen.1005164.g010" target="_blank">Fig 10B</a>). Data represent means with SD of three experiments. * <i>P</i><0.05, ** <i>P</i><0.01, *** <i>P</i><0.001, unpaired two-tailed Student’s test. ns, non-significant.</p
Crop Science, Nov 1, 2003
Virology, 2009
Potato virus X (PVX) infection leads to certain cytopathological modifications of the host endome... more Potato virus X (PVX) infection leads to certain cytopathological modifications of the host endomembrane system. The subcellular location of the PVX replicase was previously unknown while the PVX TGBp3 protein was previously reported to reside in the ER. Using PVX infectious clones expressing the green fluorescent protein reporter, and antisera detecting the PVX replicase and host membrane markers, we examined the subcellular distribution of the PVX replicase in relation to the TGBp3. Confocal and electron microscopic observations revealed that the replicase localizes in membrane bound structures that derive from the ER. A subset of TGBp3 resides in the ER at the same location as the replicase. Sucrose gradient fractionation showed that the PVX replicase and TGBp3 proteins co-fractionate with ER marker proteins. This localization represents a region where both proteins may be synthesized and/or function. There is no evidence to indicate that either PVX protein moves into the Golgi apparatus. Cerulenin, a drug that inhibits de novo membrane synthesis, also inhibited PVX replication. These combined data indicate that PVX replication relies on ER-derived membrane recruitment and membrane proliferation.
Pathogens, Dec 10, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
bioRxiv (Cold Spring Harbor Laboratory), May 16, 2021
Regardless of the general model of translation in eukaryotic cells, a number of studies suggested... more Regardless of the general model of translation in eukaryotic cells, a number of studies suggested that many of mRNAs encode multiple proteins. Leaky scanning, which supplies ribosomes to downstream open reading frames (ORFs) by read-through of upstream ORFs, is the most major regulatory mechanism to translate polycistronic mRNAs. However, the general regulatory factors controlling leaky scanning and their biological relevance have rarely been elucidated, with exceptions such as the Kozak sequence. Here, we have analyzed the strategy of a plant RNA virus to translate three movement proteins from a single RNA molecule through leaky scanning. The in planta and in vitro results indicate that significantly shorter 5′ UTR of the most upstream ORF promotes leaky scanning, potentially finetuning the translation efficiency of the three proteins in a single RNA molecule to optimize viral propagation. Moreover, in plant endogenous mRNAs, we found that shorter UTRs were more frequently observed in uORFs of polycistronic mRNAs. We propose that the promotion of leaky scanning induced by a short 5′ UTR (LISH), together with the Kozak sequence, is a conserved gene regulation mechanism not only in viruses but also in eukaryotes. .
Viruses, Jan 8, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
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Papers by Jeanmarie Verchot