ROTAVIRUS

Abstract: A material being a dsRNA gene segment coding for the major outer capsid glycoprotein of a rotavirus.

Description: ROTAVIRUS This invention relates to rotavirus, genes, ge segments, cloned genes and segments and products obtain therefrom including diagnostic reagents and vaccines. Rotavirus is now recognized by the World Heal Organization as a major cause of infantile gastroenter ti and a high priority has been placed on control of thi disease by the production of a suitable vaccine (1). Cross neutralization tests indicate four (or possibly five) (2- serotypes of human rotavirus and animal studies appear t show little cross-protection between serotypes (5). Thus potential vaccine may have to incorporate all the know human serotypes. T-he virus serotype has recently been show to be determined by the major outer shell glycoprotein (6 10) (a virus surface protein), and the gene segments codin for this protein from a bovine (UK) and a simian (SAIl rotavirus have recently been sequenced (11,12). To dat however, no such gene from human rotavirus has bee analysed. We therefor cloned and sequenced the gene encodin this protein from a human rotavirus. Hu/5 (isolated i Melbourne, Australia) belonging to serotype 2. The present invention provides a human rotavirus gen and a cloned human rotavirus gene, the use of such genes t obtain expression of antigenic viral proteins such as i bacteri al/procaryotic or eucaryotic expression systems an the expression products obtained and further includin vaccines and diagnostic reagents obtained therefrom. The present invention also provides the dsRNA gen segment coding for the major outer capsid glycoprotein of human rotavirus and, without prejudice to the generality o the foregoing, that human rotavirus may be Hu/Austral ia/5/7 (serotype 2), a DNA copy of same, a clone thereof, or vector or a host cell containing same, peptide sequence obtained therefrom. Of particular interest are vectors suc as plas ids obtained therefrom and host cells containin same. The present invention also provides a materia comprising a nucleotide sequence coding for at least part o the major outer capsid glycoprotein of a rotavirus. In one instance the present invention provides at lea one of the nucleotide sequences from nucleotide numbers 2 - 357, 480 - 513 and 657 - 720 of a rotavirus major oute capsid glycoprotein gene. In another instance the present invention provides least one of the amino acid sequences from amino aci numbers 82 - 103, 144 - 155 and 204 - 224 for which th nucleotide sequences of a rotavirus major outer capsi glycoprotein gene code. In a particularly preferred instance the prese invention provides a material comprising a nucleoti sequence encoding, or an amino acid sequence being, a. an a ino ac d sequence of 22 amino aci commencing CLYYP and terminating TLS, b. an a ino acid sequence of 12 a ino aci commencing YD and terminating SEL, or - c. an amino ac d sequence of 21 amino aci commencing GIGC and terminating EKL, and derived from a nucleotide sequence coding for major outer capsid glycoprotein of a rotavirus. .Specific portions of cloned genes are provided by invention and the invention extends to products obtain - therefrom including anti-sera or anti-bodies prepared utilization of such amino acid sequences. This invention will be exemplified by the followi description. MATERIALS AND METHODS Virus growth and purification The human rotavirus Hu/5 (Hu/Aus tral ia /5/77) (13) w grown in MAI 04 cells and purified as described previous (14). Cloning rotavirus cDNA The procedure for producing cDNA from rotavirus dsRN and cloning it into the Pstl site of the plasmid pBR322 h been described previously by Dyall-Smith e_t ___. (15). Identi fi cati on £JF cloned copies £JF the ma or outer she glycoprotein gene of Hu/5 rotavirus Since the UK bovine rotavirus gene encoding the maj outer shel l glycoprotein (gene 8 of this virus) h previously been cloned (11), this was used to screen t Hu/5 clones. To e 1 i m i nt e .p BR322 sequences, the UK gene clone was digested with Pstl and the insert separated agarose gel e lect rophor es is . The insert was then 3 label led by nick translation ( 16) and hybridized transformant bacterial colonies which had been lysed nitrocellulose filters (17). Northern blot analyses Hu/5 dsRNA was separated on a pol yacr yl ami de gel a immobilized on am i nophenyl thioether (APT) paper as describ previously (7), except that the RNA was loaded right alo the tope of the stacki ng gel (which was not divided in wells). After transfer, the blot was cut (lengthwise) in strips and hybridized to 32 P-label led cDNA or ni translated DNA probes. Labelled cDNA was prepared from Hu segments 7, 8 and 9 dsRNA ( isolated by agarose g electrophoresi s) using reverse transcri ptase' (Life Scienc Inc. U.S.A.) and random primer DNA (prepared from ca thy us DNA) (18). Hybridization conditions were as follow blots were prehybridized for 15 m in at 60°C in 5 Denhardt's solution containing 10mM HEPES (pH 7.0), 0. SDS, 3 x SSC, lOmug/ l . c o 1 i tRNA, and 18mug/ml herri sperm DNA, and -then hybridized (18 hr, 65°C) to t appropriate DNA probe. Blots were washed twice for 15 min 60°C in 0.2 x SSC containing 0.1% SDS, and exposed to x-r film. DNA sequencing The pBR322 clone was digested with Pstl, and the inse subcloned into the Pstl site of Ml 3 pδ (19). Sequences we determined from the M13 ssDNA template by the cha termination method (20) using exonuclease Ill-treat restriction fragments (except the EcoRI/Taql fragment) primers (21). A synthetic pri mer ( 5 '-dGGTCACAT-3 ' complementary to the 3 1 end of the mRNA-sense strand w also used. Electrophoresi s of rotavirus dsRNA dsRNA was extracted from purified virus preparatio using a simpl fied version of the method of Herring e; al (22). Briefly, 5mul of a purified virus suspension was adde to 200mul of 0.1 M sodium acetate buffer (pH5.0) containin 1% sodium dodecyl- sul phate (SDS) and vortexed for 1 min wit an equal volume of 'phenol '/ch loro form mixture. The phase were separated by a brief ce ntri f ugati on (2 1 , 10,000 g) an an aliquot of the aqueous phase (5-20mul) mixed with 20mu of sample buffer (25% (v/v) glycerol, 0.2% bromphenol blue 0.4M Tris-CI (pH6.8)) and analysed on a 10% pol yacryl amid 'gel (0.75 mm thick) using the buffer system of Laemmli (23 (but without SDS). The gel was silver stained according t the method of Herring et a_J_. (22), except that th incubation in silver nitrate was for 30 min instead of 2 hr and sodium borohydr de was omitted from the developin solution. Degassing of solutions was also found to b unnecessary. RESULTS AND DISCUSSION Reference will be made to the accompanying drawings i which:- Fi gu re J_ is po lyacry lam i de gel el ectrophoresi s o rotavirus dsRNA extracted from A, Wa; B, Hu/5; and C, U viruses. The eleven gene segments of Wa virus have bee numbered from largest to smallest. Figure 2 is northern blot hybridizations identifyin gene segment 8 of Hu/5 rotavirus as encoding the major oute shell glycoprotein. Track A shows part of the ethidiu bromide-stained poly aery lami de gel of Hu/5 dsRNA (onl segments 5-11 shown). The RNA bands were transferred to AP paper and the paper cut into strips (lengthwise). The blo were hybridized to 32 P-labelled DNA probes prepared from; RNA segments 7, 8 and 9 of Hu/5 virus (to precisely locat these bands); C, a pBR322 clone of UK virus segment 8 (th gene encoding the major outer shell glycoprotein of thi virus), and D, a pBR322 clone of the glycoprotein gene o Hu/5 virus. Fi gu re 3 is a summary of the sequencing strategy us to determine the nucleotide sequence of the cloned DNA co of dsRNA gene segment 8 of Hu/5 rotavirus. The number nucleotides are indicated below the line representing t clone, and the restriction sites used to generate sequenci primers are shown immediately above ( , Alul; .EcoR ,TaqI; , Bglll; , Hindi) A synthetic primer ( 5 dGGTCACAT-3 1 ), complementary to the 3' end of the mRNA-sen strand was also used (primer P). The orientation of t clone is such that the mRNA-sense DNA strand is in t indicated 5 1 to 3' direction. Figure . Is a Nucleotide sequence and predicted amin acid sequence of the mRNA-sense DNA strand of the segment clone of Hu/5 rotavirus. In phase termination codons a indicated by solid bars. Fi gu re j5. Is . a comparison of the predicted a ino-ac sequence of portion of the major outer shell glycoprotei of Hu/5 as compared to the equivalent regions of SAIl and rotavirus. . - The rotavirus genome consists of eleven dsRNA segmen which upon gel electrophoresis form a characteristic patte of bands; the virus electropherotype (24). The gel patter of genomic RNA from the human rotavirus Hu (Hu/Australia/5/77) (13), Wa (25) (human,- serotype 1) and (26) viruses are shown in Fig. 1, and demonstrate clear that Hu/5 has a "short" pattern (due to the positions segments 10 and 11) (27,14) compared to the "long" g patterns of the other two. The "short" pattern h previously been associated with serotype 2 human rotavirus (27-29), and when the Hu/5 virus was serotyped in th laboratory according to the method of Thouless et al. (3 (using typing antisera kindly supplied by M. Thouless a Wa, S2 (31) and SAIl (32) viruses as serotype 1, 2 and reference strains) (4,33) it was indeed found to belong serotype 2 (data not shown). Hu/5 genomic dsRNA was converted into DNA and clon into the Pstl site of pBR322 as described previously for rotavirus (15). Clones of the major outer shell glycoprote were identified using a probe (^ z P-labelled by ni translation) prepared from a cloned glycoprotein gene fr UK bovine rotavirus (11). The identity of one of the clones was confirmed by Northern blot analyses which als mapped this gene to segment 8 of Hu/5 rotavirus (Fig. 2 This clone was sequenced according to the strategy shown i Fig. 3 and the full sequence is shown in Fig. 4. The clon is a full-length copy of the glycoprotein gene since a) i is the same length (i.e. 1062 bp) as the corresponding U and SAIl genes, and b) it has the characteristic conserve 5' and 3 1 term nal sequences (34,35). It has one ope reading frame (the other frames contain multiple sto co.dons) capable of coding for a protein of 326 amino acid and 5' and 3 1 non-coding regions of 48 and 36 b respectively. In these respects it is identical to UK an SAIl glycoprotein genes (11,12). The base sequenc homologies of the Hu/5, SAIl and UK glycoprotein genes ar as follows; Hu/5:UK or SAIl = 74% and UK.SA11 = 77.6%. The are obviously closely related. - When the predicted amiπo-acid sequence of the Hu/ virus glycoprotein gene was compared to those of UK and SAI (Fig. 5) an even greater degree of similarity was observe In pair-wise comparison the amino-acid sequence homologi are; * Hu/5:UK - 75.8%, Hu/5:SA11 = 75.2% and UK.SA11 = 85.6 Studies with UK and SAIl viruses have shown that th gl ycosyl ation of these proteins is asparagi ne-1 in ked an consists of simple ("high mannose") ol igosaccharide moieti (36-38). Studies show that all three proteins retain potential g ly cosy lati on site (of the type Asn-X- jn ^ er ) residue 69, which for SAIl is the only such site. The Hu and UK proteins also have potential sites at residues 2 (both), 146 (Hu/5) and 318 (UK), however the distribution carbohydrate in these proteins is not known. All glycoproteins of eukaryotic cells require a sign sequence for vectorial transport across the endoplasmi reticulum (39). Using the general rules proposed by Perlm and Halvorson (40) a typical signal sequence can discerned in the first 25 residues of the 3 rotavir glycoproteins. Their putative hydrophobic core sequenc (res. 6-19) are preceded by the charged residue Glu- (re 5). The likely cleavage sites are after serine at positi 15, or after position 25 (Ser/Thr). Recent studies wi SA11 virus (41) have demonstrated a cleaved signal sequen for this protein with .a molecular weight (1.500M consistent with the earlier predicted cleavage site. It interesting that the first 25 residues of all thr glycoproteins show relatively greater conservation than t subsequent 25. While the glycoproteins of Hu/5, UK and SAIl are ve similar in ami no-acid sequence, they must differ an.ti geni ca 11 y significant regions since the three virus are serotypical 1y different, i.e. Hu/5 is a human serotype virus, UK belongs to a bovine serotype (33), and SA although of simian origin is s er ol og i cal ly human type (33). Results of competition experiments using monoclon antibodies to SAIl virus have demonstrated only one possibly two epitqpes involved in neutralization (42). - To locate -the major ant i genie regions of t glycoprotein we have used monoclonal antibodies whi neutralize SAIl rotavirus. By selecting mutants resistant neutralization and sequencing their glycoprotein genes were able to identify three (A, B and C) important regio (M.L. Dyall-S ith, I. Lazdins, G.W. Tregear and I.H. Holme -manuscript in preparation for publication). These are ami acids 82 - 103^, 144 - 155^ B ) and 204 - 224< C ), at whi region C appears to be the most important. A mutation in t C region at amino acid 211 caused a ten fold decrease in t ability of polyclonal antiviral antiserum to neutrali virus, indicating that this is a site of major antigeni importance. The sequence data (above) support the wealth serological evidence (43-45) that rotaviruses are a close related group. Indeed they appear to be much more closel related than the three serotypes of mammalian reoviru which are structurally and epi demi ol og ical ly similar rotaviruses (46). The genes encoding the serotype-speci f protein of the three reovirus serotypes are related only the extent of 1-12% (47). The fact that two simi rotaviruses, SA11 and rhesus (MM18006) are serologicall closely related (33) yet were isolated over 20 years apar (48,49) also suggests that rotavirus serotypes are fairl stable antigenical ly, unlike influenza A subtypes which sho antigenic drift (50). While many more rotavirus glycoprotei genes need to be studied, the limited number of huma serotypes so far detected and the apparently low level o antigenic drift look encouraging for the development o human rotavirus vaccines. Concerning vaccine preparation, in general it will b best if the rotavirus genetic material of this invention i introduced into a bacterium and this may be effected i accordance with the procedures of Formal et al (51), Silhav et al (52) or Roberts et al (53). REFERENCES 1. Bull. W.H.O. (1983) 61, 251-254. 2. Sato, K., Inaba, Y., iura, Y., Tokuhisa, S. an Matumoto, M. (19.82). Arch. Virol..73, 45-50. 3. Thouless, M.E., .Beards, M. and Flewett, T.H. (1982 Arch. Virol. 73, 219-230. 4. Wyatt, R.G., James, H.D., Pittman, A.L., Hoshino, Y Greenberg, H.B., Kal ica, A.R., Flores, J. and Kapikia A. Z. (1983). J. Clin. Micro. 18, 310-317. 5. Gaul, S.K., Simpson, T.F., Woode, G.N. and Fulton, R. (1982). J. Clin. Micro. 16, 495-503. 6. Kalica, A.R., Greenberg, H.B., Wyatt, R.G., Flores, J Sereno, M.M., Kapi kian, A.Z. and Chanock, R.M. (1981 Virology 112, 385-390. 7. Dyall-Smith, M.L., Azad, A. A. and Holmes, I.H. (1983 J. Virol. 46, 317-320. 8. 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(1976 Biochim. Biophys. Acta 442, 324-330. 19. -Messing, J., Crea, R. and Seeberg, P.H. (1981). Nuclei Acids Res. 9, 309-321. 20. Sanger, F., Nicklen, S. and Coulson, A.R. (1977). Pro Natl. Acad. Sci. U.S.A. 74, 5463-5467. 21. Smith, A.J.H. (1979). Nucleic Acids Res. 6, 831-848. 22. Herring, A.J., Inglis, N.F., Ojeh, C.K., Snodgrass D.R. and Menzies, J.D. (1982)-. J. Cl in. M ierobiol. 16 473-477. 23. Laemml i, U.K. (1970). Nature 227, 680-685. 24. Holmes, I.H. (1983). In "Reoviridae" (ed. W.K. Joklik p.365-367 (Plenum, New York). 25. Wyatt, R.G., James, W.D., Bohl , E.H., Thei l , K.W. Saif, L.J., Kal ica, A.R., Greenberg, H.B., Kapi kian A.I. and Chanock, R.M. (1980). Science 207, 189-191. 26. Woode, G.N., Bri dger, J.C., Hall, G. and Dennis, M.J (1974). Res. Vet. Sci. 16, 102-105. 27. Rodger, S.M., Bishop, R.F., Birch, C, McLean, B. an Holmes, I.H. (1981). J. Clin. Mierobiol. 13, 272-278. 28. Kal ica, A.R., Greenberg, H.B., Espejo, R.T., Flores J., Wyatt, R.G., Kapi kian, A. Z. and Cha nock, R.M (1981). Infect. Immun. 33, 958-961. 29. Beards, G.M. (1982). Archiv. Virol. 74, 65-70. 30. Thouless, M.E., Beards, G.M. and Flewett, T.H. (1982) Arch. Virol. 73, 219-230. 31. Urasawa, S., Urasawa, T. and Taniguchi, K. (1982) Infect. Immun. 38, 781-784. 32. Rodger, S.M., Schnagl, R.D. and Holmes, I.H. (1977). J Virol. 24, 91-98. 33. Wyatt, R.G., Greenberg, H.B., James, W.D., Pitt an A.L., Kal ica, A. R., Fl ores, J., Chanock, R.M. an Kapi kian, A.Z. (1982). Infect. Immun. 37, 110-115. 34, Clarke, I.N. and McCrae, M.A. (1983). J. Gen. Virol 64, 1877-1884. 35. Imai, M., Akatani, K., Ike garni, N. and Furuichi, Y (1983). J. Virol. 47, 125-136. 36. Ericson, B. L. , Graham, D.Y. Mason, B. B. and Estes, M.K (1982). J. Virol. 42, 825-839. 37. Arias, C.F., Lopez, S. and Espejo,. R.T. (1982). J Viro-I. 41, 42-50. 38. McCrae, M.A. and Fau 1 kner-Val 1 e, G.P. (1981). J. Virol 39, 490-496. 39. Kreil, G. (1981). Annu. Rev. Biochem. 50, 317-34-8. 40. Perlman, D. and Halvorson, H.O. (1983). J. Mol. Biol 167, 391-409. 41. Ericson, B.L., Graham, D.Y., Mason, B.B. Hanssen, H.H and Estes, M.K. (1983). Virology 127, 320-332. 42. Sonza, S., Breschkin, A.M. and Holmes, I.H. (1984 Virology 134, 318-327. 43. Kapi kian, A.Z., Cline, W.L., Kim, H.W., Kalica, A.R. Wyatt, R.G. van Kirk, D.H., Channock, R.M., James H.D., Jr. and Vaughn, A. L. (1976). Proc. Soc. Ex Biol. Med. 152, 535-539. 44. Woode, G.N., Bridger, J.C., Jones, J.M., Flewett, T.H. Bryden, A.S., Davies, H.A. and White. G.B.B. (1976 Infect. Immunol. 14, 804-810. 45. Thouless, M.E., Bryden, A.S., Flewett, T.H. Woode G.N., Bridger, J.C., Snodgrass, D.R. and Herring, J. (1977). Arch. Virol. 53, 287-294. 46. Jokl ik, W.K. (1983). In "The Reoviridae" (ed. W. Joklik) p.1-7 (Plenum, New York, (1983). 47. Gail lard, R. K. and Jokli k, W.K. (1982). Virology 12 152-164. 48. Malherbe, H.H. and St ri ck la nd-C ho 1 m ley, M. (1967 Arch. Gesamte Virusforsch. 22, 235-245. 49. Stuker, G., Oshiro, L.S. and Schmidt, N.J. (1980). J Clin. Mierobiol. 11, 202-203. 50. Both, G.W., Sleigh, M.J., Cox, N.J. and Kendal, A. (1983). J. Virol. 48, 52-60. 51. S.B. Formal, L.S. Baron, D.J. Kopecko, 0. Washington C. Powell and C.A : Life (1981). Construction of a potentia bivalent vaccine strain = introduction of Shigella sonne form 1 antigen genes into the gal E Salmonella typhi Ty 21 typhoid vaccine strain. Infect. Immun. 3_ , 746-750. 52. T.J. Silhavy, H.. Shumn, J. Beckwith and M. Schwart (1977). Use of gene fusions to study outer membrane protei localization in Escherichia co1 i. Proc. Natl. Acad. Sci. US 74, -5411-5415. 53. T.M. Roberts, I. Birel, R. R. Yocum, D.M. Livingston an M. Ptashne (1979) Synthesis of simian virus 40 antigen i JEs_£iier c_] .a > c_ lj_. Proc. Natl. Acad. Sci. USA 1, 5596-5600 The cl ai ms form part of the disclosure of thi specification. Modifications and adaptations may- be made to the abov described without departing from the spirit and scope o this invention which includes every novel feature an combination of features disclosed herein.

Claims: The claims defining the invention are as follows: 1. A material being a dsRNA gene segment coding for the major outer capsid glycoprotein of a rotavirus. 2. A material being a DNA copy of the material of claim 1, or a clone thereof, or a vector or a host cell containing same. 3. A material comprising a nucleotide sequence coding for at least part of the major outer capsid glycoprotein of a rotavirus. 4. A material as claimed in claim 3 and comprising at least one of the nucleotide sequences from nucleotide numbers 291 - 357, 480 - 513 and 657 - 720 of a rotavirus major outer capsid glycoprotein gene. 5. A material as claimed in claim 3 or claim 4, wherein the rotavirus is Hu/Australia/5/77. 6. A material as claimed in claim 3 and comprising a least one of the nucleotide sequences from nucleotide numbers 291 - 357, 480 - 513 and 657 - 720 represented in Fig. 4 of the accompanying drawings. 7. A material as claimed in claim 3, which comprises th nucleotide sequence represented in Fig. 4 of th accompanying drawings. 8. A material comprising an amino acid sequence forming a least part of the major outer capsid glycoprotein of rotavirus. 9. A material as claimed in claim 8 and comprising a least one of the amino acid sequences from amino aci numb'ers 82 - 103, 144 - 155 and 204 - 224 for which th nucleotide sequences of a rotavirus major outer capsi glycoprotein gene code. 10. A material as claimed in claim 8 or claim 9, wherei the rotavirus is Hu/Australia/5/77. 11. A material as claimed in claim 8 and comprising a least one of the amino acid sequences represented in Fig. of the accompanying drawings. 12. A material comprising a nucleotide sequence encodin or an amino acid sequence being, a. an amino ac d sequence of 22 amino acid commencing CLYYP and terminating TLS, b. an a i no aci d sequence of 12 amino aci d commencing YD and terminating SEL, or c. " an a i no aci d sequence of 21 amino acid commencing GIGC and terminating EKL, and derived from a nucleotide sequence coding for major outer capsid glycoprotein of a rotavirus. 13. A vaccine, diagnostic reagent or expression product obtained from a material in accordance with any precedin claim. 14. A bacterium comprising rotavirus genetic material an capable of producing at least one of the amino aci sequences of any one of claims 8 - 12. 15. A material in accordance with any preceding claim an substantially as hereinbefore descri bed with reference t any one of the exemplification. 16. The articles, things, parts, elements, steps, features methods, processes, compounds and compositions referred . t or indicated in the specification and/or claims of th appl ication individually or col lectively, and any and al combinations of any two or more of such.

Inventors: DYALL-SMITH MICHAEL LEIGH, HOLMES IAN HAMILTON, DYALL-SMITH, MICHAEL, LEIGH, HOLMES, IAN, HAMILTON
Applicants: UNIV MELBOURNE, THE UNIVERSITY OF MELBOURNE
Application year: 1985
Main classification: C12N1
IPC codes: A61K39, C07H21, C07K7, C07K14, C12N1, C12N15, C12P21