Interactions of the nucleocapsid protein with the 3' and 5' noncoding regions of genomic RNA of avian infectious bronchitis virus /
The IBV nucleocapsid (N) protein was expressed as a fusion protein with a 6-histidine tag. Using RNA overlay protein blot analyses and gel shift assays, the recombinant protein was shown to bind specifically to RNA fragments in the 3' conceding region of the IBV genome, whereas no interactions...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1999.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=733678681&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The IBV nucleocapsid (N) protein was expressed as a fusion protein with a 6-histidine tag. Using RNA overlay protein blot analyses and gel shift assays, the recombinant protein was shown to bind specifically to RNA fragments in the 3' conceding region of the IBV genome, whereas no interactions were observed between the same RNAs and bovine serum albumin or allantoic fluid protein. The interactions of the fusion protein with EF, a region from 78 to 217 nt from the 3' terminus of the IBV genome, CD which consisted of the 3' were weaker than interactions with fragment terminal 155 nt. The polypeptides extending from 1-91, 1-171, 1-274, 203-409 and 268-407, and the whole N protein interacted with G RNA while a polypeptide corresponding to residues 101 to 283 in the middle region did not. The polypeptides from the amino and carboxyl termini shifted the G RNA probe very efficiently while the polypeptides corresponding to the middle region did not. The intact N protein and the carboxyl terminus shifted the G RNA more efficiently than the polypeptides from the amino terminus. However, the polypeptide from the middle region was found to interact with the conceding region. RNA sequences wick interacted with the N protein were found to be uridylate-rich. One RNA sequence which did not interact with the N protein and polypeptides contains only three uridylates although it forms a stem- loop. Randomizing an U-rich sequence and reducing the uridylates percentage from 46% to 31% did not abolish the binding activities. Data obtained in this study indicated that the N protein interacted specifically with the IBV RNA sequences in the 3' and 5' conceding regions. The N protein can be divided into three domains: amino, middle and carboxyl. The domains at the amino and carboxyl termini interact with the RNA sequences in the 3' conceding regions and the one in the middle interacts with the 5' nonvoting region. Stem-loops are not essential for RNA-protein interaction. Uridylate-rich RNA sequences are the favorable sites for the N protein binding. |
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| Item Description: | Vita. "Major Subject: Veterinary Microbiology". In title, numerals are used. |
| Physical Description: | xi, 105 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 93-104). |