PUBLICATION
Cloning and characterization of mr-s, a novel SAM domain protein, predominantly expressed in retinal photoreceptor cells
- Authors
- Inoue, T., Terada, K., Furukawa, A., Koike, C., Tamaki, Y., Araie, M., and Furukawa, T.
- ID
- ZDB-PUB-060323-19
- Date
- 2006
- Source
- BMC Developmental Biology 6: 15 (Journal)
- Registered Authors
- Keywords
- none
- MeSH Terms
-
- Retina/physiology*
- Recombinant Fusion Proteins/metabolism
- Mice
- Cell Line
- Repressor Proteins/genetics*
- Repressor Proteins/metabolism
- Homeodomain Proteins/genetics*
- Homeodomain Proteins/metabolism
- Cloning, Molecular
- Pineal Gland/physiology
- Eye Proteins/genetics*
- Eye Proteins/metabolism
- Polycomb-Group Proteins
- Trans-Activators/genetics*
- Trans-Activators/metabolism
- Photoreceptor Cells/physiology*
- Otx Transcription Factors/genetics*
- Otx Transcription Factors/metabolism
- Animals
- Rats
- PubMed
- 16539743 Full text @ BMC Dev. Biol.
Citation
Inoue, T., Terada, K., Furukawa, A., Koike, C., Tamaki, Y., Araie, M., and Furukawa, T. (2006) Cloning and characterization of mr-s, a novel SAM domain protein, predominantly expressed in retinal photoreceptor cells. BMC Developmental Biology. 6:15.
Abstract
BACKGROUND: Sterile alpha motif (SAM) domains are ~70 residues long and have been reported as common protein-protein interaction modules. This domain is found in a large number of proteins, including Polycomb group (PcG) proteins and ETS family transcription factors. In this work, we report the cloning and functional characterization of a novel SAM domain-containing protein, which is predominantly expressed in retinal photoreceptors and the pineal gland and is designated mouse mr-s (major retinal SAM domain protein). RESULTS: mr-s is evolutionarily conserved from zebrafish through human, organisms through which the mechanism of photoreceptor development is also highly conserved. Phylogenetic analysis suggests that the SAM domain of mr-s is most closely related to a mouse polyhomeotic (ph) ortholog, Mph1/Rae28, which is known as an epigenetic molecule involved in chromatin modifications. These findings provide the possibility that mr-s may play a critical role by regulating gene expression in photoreceptor development. mr-s is preferentially expressed in the photoreceptors at postnatal day 3-6 (P3-6), when photoreceptors undergo terminal differentiation, and in the adult pineal gland. Transcription of mr-s is directly regulated by the cone-rod homeodomain protein Crx. Immunoprecipitation assay showed that the mr-s protein self-associates mainly through the SAM domain-containing region as well as ph. The mr-s protein localizes mainly in the nucleus, when mr-s is overexpressed in HEK293T cells. Moreover, in the luciferase assays, we found that mr-s protein fused to GAL4 DNA-binding domain functions as a transcriptional repressor. We revealed that the repression activity of mr-s is not due to a homophilic interaction through its SAM domain but to the C-terminal region. CONCLUSIONS: We identified a novel gene, mr-s, which is predominantly expressed in retinal phtoreceptors and pineal gland. Based on its expression pattern and biochemical analysis, we predict that mr-s may function as a transcriptional repressor in photoreceptor cells and in pinealocytes of the pineal gland.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping