The Parvovirinae are small non-enveloped icosahedral viruses that are important pathogens in many animal species including humans. They possess 5kb linear single-stranded DNA (ssDNA) genomes and their replication relies extensively on host nuclear factors. Our recent work has shown how the expression profiles of many of the parvoviruses feature impressively intricate processes of transcriptional transactivation, alternative RNA processing, and alternative translation initiation, which maximize their coding capacity. We have identified three aspects critical for parvovirus replication to pursue in this application. 1. Unlike AAV2, AAV5 Rep-encoding P19-generated transcripts are polyadenylated within the central intron and therefore not spliced, precluding an AAV2-like mechanism for making both Rep 40 and Rep52. Surprisingly, AAV5 ensures the production of the essential Rep 40-like protein by utilizing a new internal translation initiation event. The 150 nt RNA region lying between the two AUGs of AAV5 functions as a novel, positively-acting signal to program internal initiation. Thus, we propose in Specific Aim I: to characterize alternative translation initiation of the AAV small rep gene. 2. Translation of the goose parvovirus (GPV) spliced rep gene mRNA initiates internally, specifically bypassing a strong initiating AUG used in unspliced RNA. Although the internal initiation choice occurs in the cytoplasm during translation, it is dictated by elements within the GPV intron not present in the translated mRNA. Alternative translation initiation of the rep-gene is directed by the splicing process itself, and by the nature of the intervening intron, and thus nuclear processing of GPV RNAs influences the translation fate of these RNAs in the cytoplasm. Therefore, we propose in Specific Aim II: to characterize how nuclear RNA processing events govern alternative translation of GPV mRNAs. 3. The capsid gene of minute virus of canines (MVC) contains a potent internal polyadenylation site, and we have recently discovered that the MVC NP1 protein is essential for the accumulation in the cytoplasm of partially-processed MVC capsid gene mRNAs that retain that site, and thus required for the production of the capsid proteins. This represents a novel way in which this parvovirus regulates access to capsid gene information. NP1 is the first parvovirus protein shown to be directly involved in RNA processing, and appears to act in a unique manner. Thus, we propose in Specific Aim III: to characterize the function of NP1, a unique viral RNA processing factor. These studies will clarify critical aspects of parvovirus gene expression and will develop new paradigms in the field. Our systems afford highly tractable, tightly controlled models that are positioned to both advance parvovirology and to deliver significant insight into fundamental aspects of gene expression.
The Parvovirinae are small non-enveloped icosahedral viruses that are important pathogens in many animal species including humans. They possess small linear single-stranded DNA (ssDNA) genomes and their replication relies extensively on host nuclear factors. Our studies will clarify critical aspects of parvovirus gene expression, develop new paradigms in the field, and deliver significant insight into fundamental aspects of gene expression.
|Cotmore, Susan F; Agbandje-McKenna, Mavis; Chiorini, John A et al. (2014) The family Parvoviridae. Arch Virol 159:1239-47|
|Sukhu, Loretta; Fasina, Olufemi; Burger, Lisa et al. (2013) Characterization of the nonstructural proteins of the bocavirus minute virus of canines. J Virol 87:1098-104|
|Li, Long; Pintel, David J (2012) Splicing of goose parvovirus pre-mRNA influences cytoplasmic translation of the processed mRNA. Virology 426:60-5|
|Farris, K David; Pintel, David J (2010) Adeno-associated virus type 5 utilizes alternative translation initiation to encode a small Rep40-like protein. J Virol 84:1193-7|
|Farris, K David; Fasina, Olufemi; Sukhu, Loretta et al. (2010) Adeno-associated virus small rep proteins are modified with at least two types of polyubiquitination. J Virol 84:1206-11|
|Chen, Aaron Yun; Cheng, Fang; Lou, Sai et al. (2010) Characterization of the gene expression profile of human bocavirus. Virology 403:145-54|
|Adeyemi, Richard O; Landry, Sebastien; Davis, Meredith E et al. (2010) Parvovirus minute virus of mice induces a DNA damage response that facilitates viral replication. PLoS Pathog 6:e1001141|
|Choi, Eun-Young; Pintel, David (2009) Splicing of the large intron present in the nonstructural gene of minute virus of mice is governed by TIA-1/TIAR binding downstream of the nonconsensus donor. J Virol 83:6306-11|
|Narvaiza, Inigo; Linfesty, Daniel C; Greener, Benjamin N et al. (2009) Deaminase-independent inhibition of parvoviruses by the APOBEC3A cytidine deaminase. PLoS Pathog 5:e1000439|
|Li, Long; Qiu, Jianming; Pintel, David J (2009) The choice of translation initiation site of the rep proteins from goose parvovirus P9-generated mRNA is governed by splicing and the nature of the excised intron. J Virol 83:10264-8|
Showing the most recent 10 out of 36 publications