Cell-specific expression of NADPH-dependent cytosolic 3,5,3'-triiodo-L-thyronine-binding protein (p38CTBP)

Abstract

We have previously shown that cytosolic 3,5,30 -triiodo-L-thyronine (T3)-binding protein (CTBP) possesses a high affinity for T3 binding in the presence of nicotinamide adenine dinucleotide phosphate in vitro, and that p38CTBP increases intracellular content of T3, and suppresses T3-mediated transactivity. Screening of mRNA expression in 73 different human tissues has demonstrated that p38CTBP mRNA is expressed at high levels in brain and heart. We have examined the intracellular localization and tissue-specific distribution of this protein by using a specific antibody against human p38CTBP. Western blotting and immunoprecipitation studies have shown that the antibody recognizes human p38CTBP. Interaction of p38CTBP with the antibody did not affect the T3-binding activity of p38CTBP, and its dimer formation in vitro. Western blotting analysis has shown that p38CTBP is expressed in brain and heart predominantly, similar to the distribution of mRNA. Immunohistochemical studies have demonstrated p38CTBP in neural cells and cardiac muscle cells. p38CTBP localizes in cytoplasm rather than in nuclei in neural cells. The evidence for the presence of tissue-specific localization of p38CTBP has indicated that p38CTBP has a tissue-specific function, such as the regulation of T3 delivery from cytoplasm to nuclei.

Expression of CRYM in different rat organs during development and its decreased expression in degenerating pyramidal tracts in amyotrophic lateral sclerosis

“…We did not find CRYM protein in other organs that have been reported to express CRYM, including the heart, liver, pancreas and skeletal muscle . However, CRYM expression is reportedly increased in the skeletal muscle of patients with facioscapulohumeral muscular dystrophy (FSHD), while the expression level is not changed in DMD, polymyositis or limb girdle muscular atrophy .…”

Microarray Analysis of Differentially Expressed Genes in the Brains of Tubby Mice

“…Notably, Pak is required for regulating axon guidance and targeting of photoreceptors in Drosophila (Hing et al, 1999). In addition, Pak 1 has been implicated in the cell survival pathway through the direct phosphorylation of the death-promoting Bad protein, suggesting that Pak 1 could be neuroprotective by preventing the apoptosis of sensory neurons in control mice (Schurmann et al, 2000;Tang et al, 2000). Although the effect of tubby on axonal guidance or neuronal migration has not been studied so far, it would be intriguing to explore the role of tubby in regulating expression of Pak 1 and its possible involvement in the processes of neuronal migration or axonal outgrowth, as well as the degeneration of sensory neurons.…”

“…CRYM is a nicotinamide adenine dinucleotide phosphate (NADPH)-dependent cytosolic 3,5,3'-triiodo-L-thyronine (T3) binding protein expressed in specific tissues including the brain, retina, and inner ear (Segovia et al, 1997;Abe et al, 2003;Suzuki et al, 2003). Although the exact functions and regulatory mechanisms of CRYM are not well understood, it has pivotal roles in organ development and cellular differentiation by affecting thyroid hormone concentration, which leads to the modification of thyroid hormone action (Suzuki et al, 2007).…”

The Retinoic Acid-responsive Proline-rich Protein Is Identified in Promyeloleukemic HL-60 Cells

“…Western Blotting and Immunohistochemical Staining-Western blotting of RARP1 was performed as described previously (9). Briefly, cells were lysed by adding lysis buffer (0.05% SDS, 1% Nonidet P-40, 150 mM NaCl, 50 mM Tris-HCl, pH 7.2, containing 1 mM phenylmethylsulfonyl fluoride).…”