Geology topics

Y. Palti

Publications and source records attributed to Y. Palti.

3 recordsLinked to original sources

USGS2007

Evolutionary history of the ABCB2 genomic region in teleosts

Gene duplication, silencing and translocation have all been implicated in shaping the unique genomic architecture of the teleost MH regions. Previously, we demonstrated that trout possess five unlinked regions encoding MH genes. One of these regions harbors ABCB2 which in all other vertebrate classes is found in the MHC class II region. In this study, we sequenced a BAC contig for the trout ABCB2 region. Analysis of this region revealed the presence of genes homologous to those located in the human class II (ABCB2, BRD2, ??DAA), extended class II (RGL2, PHF1, SYGP1) and class III (PBX2, Notch-L) regions. The organization and syntenic relationships of this region were then compared to similar regions in humans, Tetraodon and zebrafish to learn more about the evolutionary history of this region. Our analysis indicates that this region was generated during the teleost-specific duplication event while also providing insight about potential MH paralogous regions in teleosts. ?? 2006 Elsevier Ltd. All rights reserved.

Developmental and Comparative Immunology↗

USGS2006

Identification and regulatory analysis of rainbow trout tapasin and tapasin-related genes

Tapasin (TAPBP) is a key member of MHC class Ia antigen-loading complexes, bridging the class Ia molecule to the transporter associated with antigen presentation (TAP). As part of an ongoing study of MHC genomics in rainbow trout, we have identified two rainbow trout TAPBP genes (Onmy-TAPBP.a and .b) and a similar but distinct TAPBP-related gene (Onmy-TAPBP-R) that had previously only been described in mammals. Physical and genetic mapping indicate that Onmy-TAPBP.a is on chromosome 18 in the MHC class Ia region and that Onmy-TAPBP.b resides on chromosome 14 in the MHC class Ib region. There are also at least two copies of TAPBP-R, Onmy-TAPBP-R.a and Onmy-TAPBP-R.b, located on chromosomes 2 and 3, respectively. Due to the central role of TAPBP expression during acute viral infection, we have characterized the transcriptional profile and regulatory regions for both Onmy-TAPBP and Onmy-TAPBP-R. Transcription of both genes increased during acute infection with infectious hematapoeitic necrosis virus (IHNV) in a fashion indicative of interferon-mediated regulation. Promoter-reporter assays in STE-137 cells demonstrate that the trout TAPBP and TAPBP-R promoters respond to interferon regulatory factors, Onmy-IRF1 and Onmy-IRF2. Overall, TAPBP is expressed at higher levels than TAPBP-R in nai??ve tissues and TAPBP transcription is more responsive to viral infection and IRF1 and 2 binding. ?? Springer-Verlag 2006.

Immunogenetics↗

USGS2002

Status and opportunities for genomics research with rainbow trout

The rainbow trout (Oncorhynchus mykiss) is one of the most widely studied of model fish species. Extensive basic biological information has been collected for this species, which because of their large size relative to other model fish species are particularly suitable for studies requiring ample quantities of specific cells and tissue types. Rainbow trout have been widely utilized for research in carcinogenesis, toxicology, comparative immunology, disease ecology, physiology and nutrition. They are distinctive in having evolved from a relatively recent tetraploid event, resulting in a high incidence of duplicated genes. Natural populations are available and have been well characterized for chromosomal, protein, molecular and quantitative genetic variation. Their ease of culture, and experimental and aquacultural significance has led to the development of clonal lines and the widespread application of transgenic technology to this species. Numerous microsatellites have been isolated and two relatively detailed genetic maps have been developed. Extensive sequencing of expressed sequence tags has begun and four BAC libraries have been developed. The development and analysis of additional genomic sequence data will provide distinctive opportunities to address problems in areas such as evolution of the immune system and duplicate genes. ?? 2002 Elsevier Science Inc. All rights reserved.

Conference Paper↗