1
|
Divilov K, Wang X, Swisher AE, Yeoman PC, Rintoul M, Fleener GB, Schoolfield B, Langdon C, Jin L. Ostreid herpesvirus 1 latent infection and reactivation in adult Pacific oysters, Crassostrea gigas. Virus Res 2024; 339:199245. [PMID: 37839558 PMCID: PMC10613911 DOI: 10.1016/j.virusres.2023.199245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 10/17/2023]
Abstract
Ostreid herpesvirus 1 (OsHV-1) is one of the most economically important pathogens of Pacific oysters. Understanding the pathogenesis of this virus is critical to developing tools to control outbreaks on shellfish farms. OsHV-1 is genetically related to vertebrate herpesviruses, which have a lytic and a latent stage, with the latent stage capable of being reactivated to the lytic stage. Here, OsHV-1 latency in Pacific oysters was investigated in experimentally and naturally infected oysters. Lytic infection in one-year-old oysters injected with the Tomales Bay strain of OsHV-1 was detectable between 1 and 4 days post-injection (dpi) but was not detectable after 5 dpi. The injected oysters shed 1 × 102 to 1 × 104 DNA copies/ml into the water during the 4-day acute phase. Lytic shedding was not detectable in two-year-old oysters injected similarly with the same strain of OsHV-1; however, the OsHV-1 genome was detectable by qPCR in the adductor muscle, gill, mantle, and hemocytes within the first 3 dpi, after which it became undetectable. No OsHV-1 was detectable in the adductor muscle, gill, or mantle from experimentally infected oysters on days 15 and 21 post-injection or from oysters sampled 9 months after surviving an OsHV-1 mortality event; however, OsHV-1 DNA could be detected in hemocytes of both experimentally infected oysters at 21 dpi and naturally infected oysters using nested PCR. In addition, lytic viral gene transcription was detectable in hemocytes of experimentally infected oysters between 1 and 21 dpi and in hemocytes of naturally infected oysters. Furthermore, OsHV-1 reactivation from latency was induced in experimentally infected oysters at 21 dpi and in naturally infected oysters 12 months after an OsHV-1 outbreak.
Collapse
Affiliation(s)
- Konstantin Divilov
- Department of Fisheries, Wildlife, and Conservation Sciences, Coastal Oregon Marine Experiment Station, Oregon State University, Hatfield Marine Science Center, Newport, OR 97365, USA
| | - Xisheng Wang
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA
| | - Alexandra E Swisher
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA
| | - Peyton C Yeoman
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA
| | | | | | - Blaine Schoolfield
- Department of Fisheries, Wildlife, and Conservation Sciences, Coastal Oregon Marine Experiment Station, Oregon State University, Hatfield Marine Science Center, Newport, OR 97365, USA
| | - Chris Langdon
- Department of Fisheries, Wildlife, and Conservation Sciences, Coastal Oregon Marine Experiment Station, Oregon State University, Hatfield Marine Science Center, Newport, OR 97365, USA
| | - Ling Jin
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA.
| |
Collapse
|
2
|
Liu Y, Bao L, Catalano SR, Zhu X, Li X. The Effects of Larval Cryopreservation on the Epigenetics of the Pacific Oyster Crassostrea gigas. Int J Mol Sci 2023; 24:17262. [PMID: 38139089 PMCID: PMC10743806 DOI: 10.3390/ijms242417262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/30/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023] Open
Abstract
High mortalities and highly variable results during the subsequent development of post-thaw larvae have been widely considered as key issues restricting the application of cryopreservation techniques to support genetic improvement programs and hatchery production in farmed marine bivalve species. To date, few studies have been undertaken to investigate the effects of cryodamage at the molecular level in bivalves. This study is the first to evaluate the effect of larval cryopreservation on the epigenetics of the resultant progenies of the Pacific oyster Crassostrea gigas. The results show that the level of DNA methylation was significantly (p < 0.05) higher and lower than that of the control when the trochophore larvae were revived and when they developed to D-stage larvae (day 1 post-fertilization), respectively, but the level returned to the control level from day 8 post-fertilization onwards. The expression of the epigenetic regulator genes DNMT3b, MeCP2, JmjCA, KDM2 and OSA changed significantly (p < 0.05) when the trochophore larvae were thawed, and then they reverted to the control levels at the D- and later larval developmental stages. However, the expression of other epigenetic regulator genes, namely, MBD2, DNMT1, CXXC1 and JmjD6, did not change at any post-thaw larval developmental stage. For the newly thawed trochophore larvae, the amount of methylated H3K4Me1 and H3K27Me1 significantly changed, and the expression of all Jumonji orthologs, except that of Jumonji5, significantly (p < 0.05) decreased. These epigenetic results agree with the data collected on larval performances (e.g., survival rate), suggesting that the effect period of the published cryopreservation technique on post-thaw larvae is short in C. gigas.
Collapse
Affiliation(s)
- Yibing Liu
- Fisheries College, Ocean University of China, Qingdao 266003, China;
| | - Lisui Bao
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China;
| | - Sarah R. Catalano
- Aquatic Sciences Centre, South Australian Research and Development Institute, Adelaide 5024, Australia;
| | - Xiaochen Zhu
- College of Science and Engineering, Flinders University, Adelaide 5042, Australia;
| | - Xiaoxu Li
- Aquatic Sciences Centre, South Australian Research and Development Institute, Adelaide 5024, Australia;
| |
Collapse
|