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PTB binds to the 3' untranslated region of the human astrovirus type 8: a possible role in viral replication.

ABSTRACT: The 3' untranslated region (3'UTR) of human astroviruses (HAstV) consists of two hairpin structures (helix I and II) joined by a linker harboring a conserved PTB/hnRNP1 binding site. The identification and characterization of cellular proteins that interact with the 3'UTR of HAstV-8 virus will help to uncover cellular requirements for viral functions. To this end, mobility shift assays and UV cross-linking were performed with uninfected and HAstV-8-infected cell extracts and HAstV-8 3'UTR probes. Two RNA-protein complexes (CI and CII) were recruited into the 3'UTR. Complex CII formation was compromised with cold homologous RNA, and seven proteins of 35, 40, 45, 50, 52, 57/60 and 75 kDa were cross-linked to the 3'UTR. Supermobility shift assays indicated that PTB/hnRNP1 is part of this complex, and 3'UTR-crosslinked PTB/hnRNP1 was immunoprecipitated from HAstV-8 infected cell-membrane extracts. Also, immunofluorescence analyses revealed that PTB/hnRNP1 is distributed in the nucleus and cytoplasm of uninfected cells, but it is mainly localized perinuclearly in the cytoplasm of HAstV-8 infected cells. Furthermore, the minimal 3'UTR sequences recognized by recombinant PTB are those conforming helix I, and an intact PTB/hnRNP1-binding site. Finally, small interfering RNA-mediated PTB/hnRNP1 silencing reduced synthesis viral genome and virus yield in CaCo2 cells, suggesting that PTB/hnRNP1 is required for HAstV replication. In conclusion, PTB/hnRNP1 binds to the 3'UTR HAstV-8 and is required or participates in viral replication.

SUBMITTER: Espinosa-Hernandez W

PROVIDER: S-EPMC4236132 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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PTB binds to the 3' untranslated region of the human astrovirus type 8: a possible role in viral replication.

Espinosa-Hernández Wendy W Velez-Uriza Dora D Valdés Jesús J Vélez-Del Valle Cristina C Salas-Benito Juan J Martínez-Contreras Rebeca R García-Espítia Matilde M Salas-Benito Mariana M Vega-Almeida Tania T De Nova-Ocampo Mónica M

PloS one 20141118 11

The 3' untranslated region (3'UTR) of human astroviruses (HAstV) consists of two hairpin structures (helix I and II) joined by a linker harboring a conserved PTB/hnRNP1 binding site. The identification and characterization of cellular proteins that interact with the 3'UTR of HAstV-8 virus will help to uncover cellular requirements for viral functions. To this end, mobility shift assays and UV cross-linking were performed with uninfected and HAstV-8-infected cell extracts and HAstV-8 3'UTR probes ...[more]

PMID: 25406089

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Dataset Information

PTB binds to the 3' untranslated region of the human astrovirus type 8: a possible role in viral replication.

Publications

PTB binds to the 3' untranslated region of the human astrovirus type 8: a possible role in viral replication.

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