Biomedical subjects

Y Hagiwara

Publications and source records attributed to Y Hagiwara.

At least 19 recordsLinked to original sources

PubMed2000

Cross-protection against a lethal influenza virus infection by DNA vaccine to neuraminidase.

Cross-protection against a lethal influenza virus infection was examined in BALB/c mice immunized with plasmid DNAs encoding the neuraminidase (NA) from different subtype A viruses. Each NA-DNA was administered twice, 3 weeks apart, at the dose of 1 microg per mouse by particle-mediated DNA transfer to the epidermis (gene gun) or at a dose of 30 microg per mouse by electroporation into the muscle. Three weeks after the second vaccination, the mice were challenged with lethal doses of homologous or heterologous viruses and the ability of each NA-DNA to protect the mice from influenza was evaluated by determining the lung virus titers, body weight and survival rates. The H3N2 virus NA-DNA conferred cross-protection against lethal challenge with antigenic variants within the same subtype, but failed to provide protection against infection by a different subtype virus (H1N1). The degree of cross-protection against infection was related to titers of the cross-reacting antibodies. These results suggest that NA-DNA can be used as a vaccine component to provide effective protection against infection not only with homologous virus but also with drift viruses.

Amino Acid Sequence↗

PubMed2000

Different activation of vascular mitogen-activated protein kinases in spontaneously and DOCA-salt hypertensive rats.

Regulation mechanisms of the activity of vascular mitogen-activated protein (MAP) kinases, enzymes believed to be involved in the pathway for cell proliferation, may be altered in hypertension. To examine whether vascular MAP kinase activation mechanisms are altered in hypertension, we measured the activity of MAP kinases in rat aorta strips from spontaneously hypertensive rats (SHR) and from deoxycorticosterone acetate (DOCA)-salt hypertensive rats, and examined whether vascular angiotensin and endothelin systems are responsible for the alteration of MAP kinase activation in these hypertensive models. Endothelium-denuded aorta strips were incubated at 37 degrees C in medium. MAP kinase activity after incubation was increased in rat aorta strips. The MAP kinase activation was greater in 9- and 15-week-old SHR aorta strips than in age-matched Wistar Kyoto rats (WKY) aorta strips. Similarly, MAP kinase activation was enhanced in aorta strips from DOCA-salt hypertensive rats. In aorta strips from these kinds of rats, the angiotensin receptor antagonist, losartan, and the endothelin receptor antagonist, cyclo (D-alpha-aspartyl-L-prolyl-D-valyl-L-leucyl-D-tryptophyl) (BQ123), inhibited the MAP kinase activation. The losartan-induced, but not BQ123-induced, inhibition of MAP kinase activation was enhanced in 15-week-old SHR aorta strips, whereas the BQ123-induced, but not losartan-induced, inhibition of MAP kinase activation was enhanced in DOCA-salt hypertensive rat aorta strips. Angiotensin II-induced MAP kinase activation was enhanced in 15-week-old SHR aorta strips, whereas it was depressed in DOCA-salt hypertensive rat aorta strips. These results indicate that MAP kinase activation function is enhanced in aorta strips from both kinds of hypertensive rats. It appears that the enhancement of MAP kinase activation results partly from enhanced vascular angiotensin system in SHR and from enhanced vascular endothelin system in DOCA-salt hypertensive rats.

Angiotensin II↗

PubMed2000

An angiotensin system in the anterior hypothalamic area anterior is involved in the maintenance of hypertension in spontaneously hypertensive rats.

An overactive brain renin-angiotensin system is one of the factors contributing to the pathogenesis of hypertension in spontaneously hypertensive rats (SHR). We examined brain sites where enhanced activity of an angiotensin system is responsible for the pathogenesis of hypertension in SHR. The angiotensin receptor antagonist, losartan was injected into tissues around rostral parts of the third ventricle in conscious rats. Losartan (0.22 nmol) injected into the anterior hypothalamic area, anterior (AHA) produced a depressor response in SHR but not in Wistar Kyoto rats (WKY). Angiotensin II (0.091-0.91 pmol) injected into the AHA produced a pressor response in both WKY and SHR, and the pressor response to angiotensin II was greater in SHR than that of WKY. Carbachol (3 pmol) injected into the AHA also produced a pressor response in WKY and SHR, and the pressor response to carbachol was almost the same in both strains of rats. Release of angiotensin peptides in the AHA was greater in SHR than that of WKY. These findings suggest that an angiotensin system in the AHA is enhanced and this enhancement of angiotensin system is involved in the maintenance of hypertension in SHR. Both increased pressor reactivity to angiotensin II and increased release of angiotensin peptides in the AHA appear to be related to this enhancement of angiotensin system in SHR.

Angiotensin II↗

PubMed2000

Induction of innate immunity by nasal influenza vaccine administered in combination with an adjuvant (cholera toxin).

Inactivated influenza vaccine was administered intranasally to BALB/c mice together with an adjuvant (cholera toxin B subunit [CTB] supplemented with a trace amount of the whole toxin, CTB*) and its ability to induce innate immunity and confer protection against influenza was examined. Nasal wash virus titres 3 days after inoculation of homologous viruses were measured as an index of the ability of the vaccine to confer protection in mice immunized with either CTB*-combined vaccine or CTB* alone 1-21 days previously. The results were as follows. (1) Partial but significant reduction of the nasal-wash virus titres (prevention) was detected beginning 3 days after the vaccination, that is, 2 days earlier than the appearance of both virus-specific antibody-forming cells (AFCs) in the nasal-associated lymphoid tissue (NALT) and virus-specific IgA antibody responses in the nasal washes of mice immunized with the CTB*-combined vaccine. (2) The protection, detected on day 3 and peaking on day 5 but lost by day 21, was also conferred in mice immunized with CTB* alone. (3) The non-specific prevention was detected at doses of more than 0.3 microg of CTB*/mouse. (4) The nonspecific protection beginning 3 days after the immunization involved the enhanced expression of cytokine mRNAs (IL-15 and IL-18), considered responsible for natural killer (NK) cell activation, by the non-T cell populations in the NALT. (5) Normal NALT cells, when cultured in vitro with CTB*, secreted IL-1beta within a few hours in culture. These results demonstrate that the CTB*-combined vaccine, when given intranasally into mice, can confer nonspecific protection against influenza beginning 3 days after the vaccination and that CTB* also possessed this ability to confer protection non-specifically and temporarily by inducing the secretion of IL-1beta, one of the most important cytokines that initiates both innate and adaptive immunity, and also NK cell activity.

Adjuvants, Immunologic↗

PubMed2000

Genetic analysis of the cell-to-cell movement of beet yellows closterovirus.

A beet yellows closterovirus (BYV) variant expressing green fluorescent protein and leaves of BYV local lesion host Claytonia perfoliata were used to reveal genetic requirements for BYV cell-to-cell movement in leaf epidermis and mesophyll. A series of mutations targeting genes that are not involved in amplification of the viral positive-strand RNA was analyzed. The products of genes coding for a 6-kDa hydrophobic protein (p6) and a 64-kDa protein (p64), as well as for minor and major capsid proteins, were found to be essential for intercellular translocation of BYV. In a previous work, we have demonstrated that the BYV HSP70-homolog (HSP70h) also plays a critical role in viral movement (V. V. Peremyslov, Y. Hagiwara, and V. V. Dolja, 1999, Proc. Natl. Acad. Sci. USA, 96, 14771-14776). Altogether, a unique protein quintet including three dedicated movement proteins (p6, p64, and HSP70h) and two structural proteins is required to potentiate the cell-to-cell movement of a closterovirus. The corresponding BYV genes are clustered in a block that is conserved among diverse representatives of the family Closteroviridae.

Capsid↗

PubMed2000

The effect of mitomycin C trabeculectomy on the progression of visual field defect in normal-tension glaucoma.

BACKGROUND: We investigated in a prospective fashion the visual prognosis and complications in normal-tension glaucoma following unilateral trabeculectomy with adjunctive mitomycin C. METHODS: Trabeculectomy with adjunctive mitomycin C was carried out unilaterally in 21 cases of normal-tension glaucoma. Intraocular pressure (IOP), visual prognosis, and complications were compared between the operated eyes and the non-operated fellow eyes. The follow-up period ranged from 2 to 7 years. RESULTS: The IOP dropped significantly from 14.8+/-1.8 mmHg (mean +/- SD) to 9.6+/-3.9 mmHg in the operated eyes (P=0.0002, Wilcoxon signed-rank test), but did not drop in the non-operated eyes. The mean deviation (MD) was -12.69+/-6.41 dB preoperatively and -14.70+/-5.49 dB at the last clinic visit in the operated eyes, whereas in non-operated eyes it was -7.85+/-5.65 dB and -11.15+/-5.62 dB, respectively. The MD deteriorated significantly in both operated and non-operated eyes (operated eyes P=0.0239, non-operated eyes: P=0.0002; Wilcoxon signed-rank test). The MD slope was -0.37+/-0.60 dB/year and -0.71+/-0.89 dB/year for the operated and non-operated eyes, respectively (P=0.5243, Mann-Whitney U-test). Visual field deterioration was more frequently observed in the non-operated eyes by a pointwise definition of the progression (P<0.05, McNemar test). Visual acuity deteriorated in 6 of the operated eyes and in 5 of the non-operated eyes. Cataract developed in 6 (29%) of the 21 operated eyes, while among the non-operated eyes 4 (19%) developed cataract. CONCLUSION: Mitomycin C trabeculectomy is effective in delaying progression of visual field defect in normal-tension glaucoma, but complications may arise and cause some visual disturbance.

Adult↗

PubMed2000

Human tissue distribution of TA02, which is homologous with a new type of aspartic proteinase, napsin A.

The N-terminal amino acid sequence of TA02 (molecular weight 35.0 kDa, isoelectric point 5.29), which is associated with primary lung adenocarcinoma, was determined and a fragment peptide was used to generate mouse monoclonal antibodies (mAbs) against TA02. The amino acid sequence suggested that TA02 might be homologous with napsin A, a new type of aspartic proteinase. In this context, we confirmed the expression of napsin A in primary lung adenocarcinoma using reverse-transcription polymerare chain reaction (RT-PCR) and showed that the TA02 mAbs reacted with glutathione-S-transferase (GST)-napsin A fusion protein. We concluded that TA02 is the same molecule as napsin A, and showed immunohistochemically that it is distributed mainly in type II pneumocytes, alveolar macrophages, renal tubules and exocrine glands and ducts in the pancreas. In particular, type II pneumocytes and alveolar macrophages showed high expression of TA02 among human normal tissues. In primary lung adenocarcinoma, 47 out of 58 (81.0%) primary lesions were positive. All well-differentiated adenocarcinomas except those of goblet cell type showed high expression of TA02. In addition, two out of seven (28.6%) large cell carcinomas showed low expression of TA02. The other histopathological types of primary lung cancer did not express TA02 at all. A few cases of renal cell cancer, pancreatic cancer, breast cancer, thyroid cancer, colon cancer and ovarian cancer showed low expression, but the staining patterns were completely different from that of primary lung adenocarcinoma, which showed a granular staining pattern. Our novel mAbs should be valuable for immunochemical detection of TA02/napsin A.

Adenocarcinoma↗

PubMed2000

Blockade of angiotensin receptors in the anterior hypothalamic preoptic area lowers blood pressure in DOCA-salt hypertensive rats.

It has been established that deoxycorticosterone acetate (DOCA)-salt hypertensive rats have an overactive brain angiotensin-system. The purpose of the present study was to identify the brain sites showing enhanced angiotensin-system activity responsible for the pathogenesis of hypertension in DOCA-salt hypertensive rats. The angiotensin receptor antagonist, losartan, was injected into brain ventricles or into tissues around the rostral parts of the third ventricle in conscious DOCA-salt hypertensive rats. Losartan (1 microg) injection into the lateral ventricle or into the rostral parts of the third ventricle produced a depressor response, whereas the agent did not affect blood pressure when injected into the caudal parts of the third ventricle or into the fourth ventricle. Losartan (0.1 microg) injection into the anterior hypothalamic preoptic area, anterior (AHA) produced a depressor response. Angiotensin II (0.1-1 ng) injection into the AHA produced a pressor response in sham-operated and DOCA-salt hypertensive rats, and the pressor response to angiotensin II (1 ng) was greater in DOCA-salt hypertensive rats than that in sham-operated rats. Release of angiotensin peptides in the AHA was greater in DOCA-salt hypertensive rats than that in sham-operated rats. These findings suggest that the angiotensin-system in the AHA is enhanced, and that this enhancement is involved in the maintenance of hypertension in DOCA-salt hypertensive rats. Both increased pressor reactivity to angiotensin II and increased release of angiotensin peptides in the AHA appear to be related to this enhancement of the angiotensin-system in DOCA-salt hypertensive rats.

Angiotensin II↗

PubMed2000

Antibodies to different peptides in osteopontin reveal complexities in the various secreted forms.

We have generated synthetic peptides corresponding to various portions of human osteopontin (OPN) and have immunized rabbits and mice with these peptides to generate polyclonal and monoclonal antibodies specific to human OPN. We then generated six distinct sandwich enzyme-linked immunoabsorbent assay (ELISA) systems by using different pairs of polyclonal and monoclonal antibodies against human OPN. These systems allowed us to detect not only various isoforms and truncated forms of recombinant OPN, but also the glycosylated form of native urinary OPN. Most importantly, tumor-derived OPN was differentially detected by the six ELISA systems. The ELISA systems that we have developed will be useful for clarifying the functional roles for OPN in vivo in various physiologic and pathologic conditions.

Adult↗

PubMed1999

HSP70 homolog functions in cell-to-cell movement of a plant virus.

Plant closteroviruses encode a homolog of the HSP70 (heat shock protein, 70 kDa) family of cellular proteins. To facilitate studies of the function of HSP70 homolog (HSP70h) in viral infection, the beet yellows closterovirus (BYV) was modified to express green fluorescent protein. This tagged virus was competent in cell-to-cell movement, producing multicellular infection foci similar to those formed by the wild-type BYV. Inactivation of the HSP70h gene by replacement of the start codon or by deletion of 493 codons resulted in complete arrest of BYV translocation from cell to cell. Identical movement-deficient phenotypes were observed in BYV variants possessing HSP70h that lacked the computer-predicted ATPase domain or the C-terminal domain, or that harbored point mutations in the putative catalytic site of the ATPase. These results demonstrate that the virus-specific member of the HSP70 family of molecular chaperones functions in intercellular translocation and represents an additional type of a plant viral-movement protein.

Adenosine Triphosphatases↗

PubMed1999

Midbrain central gray is involved in mediation of cholinergic inputs to the rostral ventrolateral medulla of the rat.

There are cholinergic inputs responsible for pressor responses in the rostral ventrolateral medulla (RVLM) and stimulation of midbrain central gray (CG) increases arterial pressure via activation of neurons in the RVLM. In this study, we examined whether the CG was involved in mediation of the cholinergic inputs to the RVLM. Male Wistar rats were anesthetized, paralyzed, and artificially ventilated. Unilateral microinjection of L-glutamate into the CG produced a pressor response. Microinjection of the muscarinic receptor antagonist scopolamine into the unilateral RVLM inhibited the pressor response to L-glutamate injected ipsilaterally into the CG, whereas microinjection of the cholinesterase inhibitor physostigmine into the RVLM enhanced it. CG stimulation also enhanced the firing rate of RVLM barosensitive neurons and the enhancement of the firing rate was inhibited by scopolamine iontophoretically applied on neurons. CG injection of L-glutamate produced a release of acetylcholine in the RVLM. Unilateral microinjection of L-glutamate into the pedunculopontine tegmental nucleus (PPT) also produced a pressor response, but the pressor response to L-glutamate was not affected by scopolamine injected ipsilaterally into the RVLM. These results provide evidence that the CG but not the PPT is involved in mediation of cholinergic inputs responsible for pressor responses in the RVLM.

Acetylcholine↗

PubMed1999

Subcellular localization of the HSP70-homolog encoded by beet yellows closterovirus.

Closteroviridae is the only viral family coding for a homolog of HSP70 (HSP70h). Polyclonal antiserum to recombinant beet yellows closterovirus (BYV) HSP70h was generated and used for immunogold labeling of the leaf samples derived from the infected Nicotiana benthamiana plants. Ultrastructural analysis revealed the preferential accumulation of BYV in phloem, although occasional infection of the leaf mesophyll cells was also observed. The strongest HSP70h-specific labeling was associated with virion aggregates and vesicles harboring scattered virions. HSP70h was also observed in close proximity of plasmodesmata and inside the plasmodesmatal channels. The possible role of the BYV HSP70h in RNA encapsidation was tested in tobacco protoplasts. A BYV mutant possessing an inactivated HSP70h gene exhibited no detectable encapsidation defects. Collectively, the obtained results suggested that closteroviral HSP70h escorts the virions to their destinations inside the infected cells and possibly participates in the intercellular translocation of BYV.

Animals↗

PubMed1999

Mutants of cholera toxin as an effective and safe adjuvant for nasal influenza vaccine.

The effectiveness and safety of mutants of cholera toxin (CT) as an adjuvant for nasal influenza vaccine was examined. Four CT mutants, called CT7 K (Arg to Lys), CT61F (Arg to Phe), CT112 K (Glu to Lys), and CT118E (Glu to Gln), were produced by the replacement of one amino acid at the A1-subunit using site-directed mutagenesis. All these mutants were confirmed to be less toxic than native CT when the toxicity was analysed by using Y1 adrenal cells in vitro. When high (1 microg) and low (0.1 microg) doses of these CT mutants, together with high (1 microg) and low (0.1 microg) doses of influenza A/PR/8/34 virus (H1N1) vaccine, respectively, were administered intranasally into BALB/c mice in a two dose regimen (twice, 4 weeks apart), they produced both anti-PR8 hemagglutinin (HA) IgA and IgG antibody (Ab) responses roughly in a dose-dependent manner. The relatively low level of anti-HA Ab responses, induced by the low dose CT mutants, were enough to provide complete protection against the homologous virus infection. Under these vaccination conditions, no anti-CTB IgE Ab responses were induced. The mutant CT112 K, which showed a relatively high adjuvant activity, the lowest toxicity and relatively high yields in a bacterial culture, seems to be the most effective and safest adjuvant for nasal influenza vaccine among those examined. The low dose of CT derivatives or vaccine used in the mouse model (0.1 microg/20 g mouse) corresponded to 100 microg/20 kg, the estimated dose per person. A tentative plan for safety standards for human use of CT (or LT) derivatives as an adjuvant of nasal influenza vaccine is discussed.

Adjuvants, Immunologic↗

PubMed1999

Vascular mitogen-activated protein kinase activity is enhanced via angiotensin system in spontaneously hypertensive rats.

The vascular structural remodeling function may be altered in genetically hypertensive animals, spontaneously hypertensive rats (SHR). To examine this possibility, we measured the activity of mitogen-activated protein (MAP) kinases, enzymes believed to be involved in the pathway for cell proliferation, in rat aorta strips, and examined whether the endothelium removal-induced MAP kinase activation function is altered in SHR and whether vascular angiotensin and endothelin systems are responsible for the alteration of MAP kinase activation in SHR. Male 4-week-old SHR and age-matched Wistar Kyoto rats (WKY) supplied by Charles River Japan were used. Endothelium-denuded aorta strips were incubated at 37 degrees C in medium. MAP kinase activity after incubation was time-dependently increased in strips from SHR and WKY. MAP kinase activation was greater in SHR than in WKY aorta strips. Similarly, MAP kinase activation was enhanced in aorta strips from 4-week-old SHR and stroke prone SHR supplied by the Diseases Model Cooperative Research Association (Kyoto, Japan). In aorta strips from SHR and WKY, the angiotensin receptor antagonist, losartan, and the endothelin receptor antagonist, cyclo (D-alpha-aspartyl-L-prolyl-D-valyl-L-leucyl-D-tryptophyl)(BQ123), caused concentration-dependent inhibition of MAP kinase activation. The losartan-induced but not BQ123-induced inhibition of MAP kinase activation was greater in SHR than in WKY aorta strips. Angiotensin II caused a concentration-dependent increase in MAP kinase activity and the angiotensin II-induced MAP kinase activation was greater in SHR than in WKY aorta strips. These results indicate that endothelium removal-induced MAP kinase activation is enhanced in aorta strips from young SHR, suggesting that vascular structural remodeling function may be enhanced in SHR. It appears that the enhancement of MAP kinase activation results, at least in part, from enhanced function of vascular angiotensin system in SHR.

Angiotensin II↗

PubMed1999

Specific sandwich-type enzyme immunoassays for smooth muscle constricting novel 31-amino acid endothelins.

We established highly sensitive and specific sandwich-enzyme immunoassays (EIAs) for three newly discovered bioactive 31-amino acid endothelins [ETs(1-31)], which can detect as little as 0.16 pg/well of ET-1(1-31), 0.39 pg/well of ET-2(1-31), and 0.16 pg/well of ET-3(1-31). The EIAs showed no crossreactivity with 21-amino acid endothelins [ETs(1-21)] or big ETs at the usual assay concentrations below 1-5 ng/ml. In reversed-phase HPLC, immunoreactive ETs(1-31) in the granulocytes of normal human subjects eluted at the exact positions of authentic ETs(1-31), except for the presence of one additional unknown immunoreactive ET-1(1-31). The results also indicate that ETs(1-31) exist in the granulocytes at levels higher than or similar to those of ETs(1-21). This study is the first to establish EIAs for novel bioactive ETs(1-31). These assays can be utilized to assess the pathophysiological roles of ETs(1-31).

Chromatography, High Pressure Liquid↗

PubMed1999

Spatiotemporal, allelic, and enforced expression of Ximpact, the Xenopus homolog of mouse imprinted gene impact.

Mouse Impact is an imprinted gene encoding an evolutionarily conserved protein of unknown function. We isolated cDNA for the Xenopus homolog of Impact (Ximpact), since the clawed frog not only provides an excellent model for the study of gene function in early development but also allows the generation of interspecific F1 hybrids required for the examination of allelic expression status. The predicted product of Ximpact shows an extreme sequence similarity to those of mouse Impact and its homologs in nematoda, fission yeast, and budding yeast. The transcript of Ximpact is present in oocytes as well as in early embryos, and its spatial distribution is ubiquitous in both embryonic and adult stages. An RT-PCR-RFLP assay using the reciprocal interspecific F1 hybrids and a DNA polymorphism between X. laevis and X. borealis showed that Ximpact is expressed biallelically when analyzed as a whole embryo. Overexpression of Ximpact by RNA microinjection resulted in a higher than normal rate of gastrulation defects, suggesting the need for tight control of its dosage in early development.

Alleles↗

PubMed1999

Effective adenovirus-mediated gene expression in adult murine skeletal muscle.

We established an efficient method for obtaining expression of a foreign marker gene transferred in vitro into myoblasts and in vivo into adult mouse skeletal muscles using adenovirus vector. After infection of the C2 myoblasts with the adenovirus vector containing the beta-actin promoter with cytomegalovirus (CMV) enhancer (CAG promoter) AxCALacZ, significantly greater number of cells express beta-galactosidase when compared with the adenovirus vector expressing the lacZ gene under the control of the SR alpha viral terminal repeat promoter (AxSRLacZL) or the myosin heavy chain (MHC) IIB promoter (AxMHCLacZ). We also injected AxCALacZ into the skeletal muscles of 5- to 6-week-old C57BL/10 mice and determined that more than 60% of their muscle fibers expressed the lacZ gene 7 days after injection. The CAG promoter may have application in the development of gene therapy for Duchenne muscular dystrophy (DMD) using adenovirus vector.

Adenoviridae↗

PubMed1999

Regulation of closterovirus gene expression examined by insertion of a self-processing reporter and by northern hybridization.

A reporter open reading frame (ORF) coding for a fusion of bacterial beta-glucuronidase (GUS) with a proteinase domain (Pro) derived from tobacco etch potyvirus was utilized for tagging individual genes of beet yellows closterovirus (BYV). Insertion of this reporter ORF between the first and second codons of the BYV ORFs encoding the HSP70 homolog (HSP70h), a major capsid protein (CP), and a 20-kDa protein (p20) resulted in the expression of the processed GUS-Pro reporter from corresponding subgenomic RNAs. The high sensitivity of GUS assays permitted temporal analysis of reporter accumulation, revealing early expression from the HSP70h promoter, followed by the CP promoter and later the p20 promoter. The kinetics of transcription of the remaining BYV genes encoding a 64-kDa protein (p64), a minor capsid protein (CPm), and a 21-kDa protein (p21) were examined via Northern blot analysis. Taken together, the data indicated that the temporal regulation of BYV gene expression includes early (HSP70h, CPm, CP, and p21 promoters) and late (p64 and p20 promoters) phases. It was also demonstrated that the deletion of six viral genes that are nonessential for RNA amplification resulted in a dramatic increase in the level of transcription from one of the two remaining subgenomic promoters. Comparison with other positive-strand RNA viruses producing multiple subgenomic RNAs showed the uniqueness of the pattern of closterovirus transcriptional regulation.

Cells, Cultured↗