ZBED4, a cone and Müller cell protein in human retina, has a different cellular expression in mouse.

Purpose: ZBED4, a protein in cones and Müller cells of human retina, may play important functions as a transcriptional activator of genes expressed in those cells or as a co-activator/repressor of their nuclear hormone receptors. To begin investigating these potential roles of ZBED4, we studied the developmental expression and localization of both the Zbed4 mRNA and protein of mouse retina.

Methods: northern blots showed the presence of Zbed4 mRNA in retina and other mouse tissues, and western blots showed the nuclear and cytoplasmic expression of Zbed4 at different developmental times.

ZBED4, a BED-type zinc-finger protein in the cones of the human retina.

Purpose: To characterize the ZBED4 cDNA identified by subtractive hybridization and microarray of retinal cone degeneration (cd) adult dog mRNA from mRNA of normal dog retina.

Methods: The cDNA library obtained from subtractive hybridization was arrayed and screened with labeled amplicons from normal and cd dog retinas. Northern blot analysis was used to verify ZBED4 mRNA expression in human retina.

Transfer of microRNAs by embryonic stem cell microvesicles.

Microvesicles are plasma membrane-derived vesicles released into the extracellular environment by a variety of cell types. Originally characterized from platelets, microvesicles are a normal constituent of human plasma, where they play an important role in maintaining hematostasis. Microvesicles have been shown to transfer proteins and RNA from cell to cell and they are also believed to play a role in intercellular communication.

Regulatory sequences in the 3' untranslated region of the human cGMP-phosphodiesterase beta-subunit gene.

Purpose: Rod cGMP-phosphodiesterase, a key enzyme in visual transduction, is important for retinal integrity and function. Mutations in the gene encoding the phosphodiesterase beta-subunit (PDEbeta) cause retinal degeneration in animals and humans. Here the authors tested the hypothesis that elements in the 3' untranslated region (3' UTR) of the PDEbeta gene are involved in the regulation of PDEbeta expression.

Translational regulation of the rod photoreceptor cGMP-phosphodiesterase: the role of the 5'- and 3'-untranslated regions.

We have established earlier that rod photoreceptor cGMP-phosphodiesterase (PDE6) alpha and beta subunits are equally represented in the retina at the protein level and have similar turnover rates. mRNA quantification revealed five PDE6beta messages for every PDE6alpha transcript pointing at post-transcriptional regulation of PDE6alpha and PDE6beta expression. Indeed, the wild-type PDE6alpha mRNA was translated 5-fold more efficiently than that of PDE6beta.

Two forms of the large tumor suppressor gene (Lats1) protein expressed in the vertebrate retina.

The large tumor suppressor gene (Lats1) encodes a protein kinase that is highly conserved from fly to human, and plays a crucial role in the prevention of tumor formation by controlling mitosis progression. We have found that in addition to the previously isolated 7.5 kb long form of Lats1 (Lats1L) mRNA, a less abundant, shorter, 3.

Differential expression of rod photoreceptor cGMP-phosphodiesterase alpha and beta subunits: mRNA and protein levels.

The catalytic core of photoreceptor-specific cGMP-phosphodiesterase (PDE) consists of two subunits, PDEalpha and PDEbeta, that are homologous and have similar domain organization but are encoded by different genes. We have examined the PDEalpha and PDEbeta mRNA steady-state and protein levels as well as the biosynthesis rate of these proteins in developing and fully differentiated retinas. We have also determined the translational efficiency of PDE subunits and the role of their mRNA structures in regulating protein synthesis.

Cloning and characterization of the canine photoreceptor specific cone-rod homeobox (CRX) gene and evaluation as a candidate for early onset photoreceptor diseases in the dog.

Purpose: The cone-rod homeobox protein (CRX) is a member of the homeodomain-containing protein family expressed in the retinal photoreceptors and pinealocytes; it is involved in the regulation of the coordinate expression of multiple photoreceptor specific genes during retinal development. Mutations in the CRX gene are causally associated with retinal degeneration phenotypes in man. To clone the full length cDNA, characterize the genomic organization of canine CRX, map the gene in a radiation hybrid (RH) panel, and evaluate it as a candidate for canine inherited retinal degenerations.