Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder
The hepatitis E virus (HEV) hypervariable region (HVR) presents the highest divergence of the entire HEV genome. It is characteristically rich in proline, and so is also known as the “polyproline region” (PPR). HEV genotype 3 (HEV-3) exhibits different PPR lengths due to insertions, PPR and/or RNA-d...
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MDPI AG
2020-09-01
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| Series: | Microorganisms |
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| Online Access: | https://www.mdpi.com/2076-2607/8/9/1417 |
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| author | Milagros Muñoz-Chimeno Alejandro Cenalmor Maira Alejandra Garcia-Lugo Marta Hernandez David Rodriguez-Lazaro Ana Avellon |
| author_facet | Milagros Muñoz-Chimeno Alejandro Cenalmor Maira Alejandra Garcia-Lugo Marta Hernandez David Rodriguez-Lazaro Ana Avellon |
| author_sort | Milagros Muñoz-Chimeno |
| collection | DOAJ |
| description | The hepatitis E virus (HEV) hypervariable region (HVR) presents the highest divergence of the entire HEV genome. It is characteristically rich in proline, and so is also known as the “polyproline region” (PPR). HEV genotype 3 (HEV-3) exhibits different PPR lengths due to insertions, PPR and/or RNA-dependent RNA polymerase (RdRp) duplications and deletions. A total of 723 PPR-HEV sequences were analyzed, of which 137 HEV-3 sequences were obtained from clinical specimens (from acute and chronic infection) by Sanger sequencing. Eight swine stool/liver samples were also analyzed. N- and C-terminal fragments were confirmed as being conserved, but they harbored differences between genotypes and were not proline-plentiful regions. The genuine PPR is the intermediate region between them. HEV-3 PPR contains a higher percentage (30.4%) of prolines than other genotypes. We describe for the first time: (1) the specific placement of HEV-3 PPR rearrangements in sites 1 to 14 of the PPR, noting that duplications are more frequently attached to sites 11 and 12 (AAs 74–79 and 113–118, respectively); (2) the cadence of repetitions follows a circular-like pattern of blocks A to J, with F, G, H, and I being the most frequent; (3) a previously unreported insertion homologous to apolipoprotein C1; and (4) the increase in frequency of potential N-glycosylation sites and differences in AAs composition related to duplications. |
| first_indexed | 2024-03-10T16:19:41Z |
| format | Article |
| id | doaj.art-87bec504889148f89f418674f0a1dd80 |
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| issn | 2076-2607 |
| language | English |
| last_indexed | 2024-03-10T16:19:41Z |
| publishDate | 2020-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Microorganisms |
| spelling | doaj.art-87bec504889148f89f418674f0a1dd802023-11-20T13:46:55ZengMDPI AGMicroorganisms2076-26072020-09-0189141710.3390/microorganisms8091417Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the DisorderMilagros Muñoz-Chimeno0Alejandro Cenalmor1Maira Alejandra Garcia-Lugo2Marta Hernandez3David Rodriguez-Lazaro4Ana Avellon5Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, SpainHepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, SpainHepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, SpainLaboratorio de Biología Molecular y Microbiología, Instituto Tecnológico Agrario de Castilla y León (ITACyL), 47071 Valladolid, SpainMicrobiology Division, Faculty of Sciences, University of Burgos, 09001 Burgos, SpainHepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, SpainThe hepatitis E virus (HEV) hypervariable region (HVR) presents the highest divergence of the entire HEV genome. It is characteristically rich in proline, and so is also known as the “polyproline region” (PPR). HEV genotype 3 (HEV-3) exhibits different PPR lengths due to insertions, PPR and/or RNA-dependent RNA polymerase (RdRp) duplications and deletions. A total of 723 PPR-HEV sequences were analyzed, of which 137 HEV-3 sequences were obtained from clinical specimens (from acute and chronic infection) by Sanger sequencing. Eight swine stool/liver samples were also analyzed. N- and C-terminal fragments were confirmed as being conserved, but they harbored differences between genotypes and were not proline-plentiful regions. The genuine PPR is the intermediate region between them. HEV-3 PPR contains a higher percentage (30.4%) of prolines than other genotypes. We describe for the first time: (1) the specific placement of HEV-3 PPR rearrangements in sites 1 to 14 of the PPR, noting that duplications are more frequently attached to sites 11 and 12 (AAs 74–79 and 113–118, respectively); (2) the cadence of repetitions follows a circular-like pattern of blocks A to J, with F, G, H, and I being the most frequent; (3) a previously unreported insertion homologous to apolipoprotein C1; and (4) the increase in frequency of potential N-glycosylation sites and differences in AAs composition related to duplications.https://www.mdpi.com/2076-2607/8/9/1417hepatitis E virusHEVPPRHVRhypervariablehyper-proline |
| spellingShingle | Milagros Muñoz-Chimeno Alejandro Cenalmor Maira Alejandra Garcia-Lugo Marta Hernandez David Rodriguez-Lazaro Ana Avellon Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder Microorganisms hepatitis E virus HEV PPR HVR hypervariable hyper-proline |
| title | Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder |
| title_full | Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder |
| title_fullStr | Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder |
| title_full_unstemmed | Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder |
| title_short | Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder |
| title_sort | proline rich hypervariable region of hepatitis e virus arranging the disorder |
| topic | hepatitis E virus HEV PPR HVR hypervariable hyper-proline |
| url | https://www.mdpi.com/2076-2607/8/9/1417 |
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