Transcript localization

Bockers TM, Segger-Junius M, Iglauer P, Bockmann J, Gun-delfinger ED, et al. 2004. Differential expression and dendritic transcript localization of Shank family members identification of a dendritic targeting element in the 3V untranslated region of Shankl mRNA. Mol Cell Neurosci 26 182-190. 

WICH hSNF2h (xISWI) Williams Syndrome Transcription Localized to heterochromatic replication foci [297]. Some ISWI remains... 

TARGETING Despite the vast complexities of eukaryotic cell structure and function, each newly synthesized polypeptide is normally directed to its proper destination. Considering that translation takes place in the cytoplasm (except for certain molecules that are produced within mitochondria and plastids) and that a wide variety of polypeptides must be directed to their proper locations, it is not surprising that the mechanisms by which cellular proteins are targeted are complex. Although this process is not yet completely understood, there appear to be two principal mechanisms by which polypeptides are directed to their correct locations transcript localization and signal peptides. Each is briefly discussed. 

Wilkie, G. S., and I. Davis. 2001. Drosophila wingless and pair-rule transcripts localize apically by dynein-mediated transport of RNA particles. Cell 105 209-219. 

One such hypotheses submits that most antidepressants enhance the expression of cyclo-AMP response element binding protein (CREB), which is a transcription factor that after phosphorylation binds to cyclo-AMP response elements localized in the promoter region of many genes including that coding for brain... 

CART (cocaine- and amphetamine-regulated transcript) is a hypothalamic peptide that inhibits both normal and starvation-induced feeding when injected into cerebral ventricles of rats. CART is co-localized with the anorexigenic peptide a-melanocyte-stimulating hormone in neurons of the arcuate nucleus. Secretion of CART is stimulated by leptin and CART may be an endogenous inhibitor of food intake. 

Sarge, K.D., Murphy, S.P., Morimoto, R.l. (1993). Activation of heat shock gene transcription by heat shock factor 1 involves oligomenzation, acquisition of DNA binding activity, and nuclear localization and can occur in the absence of stress. Mol. Cell. Biol. 13. 1392-1407. 

Alternatively, one interesting drug delivery technique exploits the active transport of certain naturally-occurring and relatively small biomacromolecules across the cellular membrane. For instance, the nuclear transcription activator protein (Tat) from HIV type 1 (HlV-1) is a 101-amino acid protein that must interact with a 59-base RNA stem-loop structure, called the traus-activation region (Tar) at the 5 end of all nascent HlV-1 mRNA molecules, in order for the vims to replicate. HIV-Tat is actively transported across the cell membrane, and localizes to the nucleus [28]. It has been found that the arginine-rich Tar-binding region of the Tat protein, residues 49-57 (Tat+9 57), is primarily responsible for this translocation activity [29]. 

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