Specificity protein 1 transcription factor

Chintharlapalli S, Papineni S, Ramaiah SK, Safe S. (2(X)7) Betuhnic acid inhibits prostate cancer growth through inhibition of specificity protein transcription factors. Cancer Res 67 2816-2823. 

The structure of eukaryotic promoters is more complex than that of prokaryotic promoters. DNA sequences, hundreds of base pairs (bp) upstream from the transcription start site, control the rate of initiation. Furthermore, initiation requires numerous specific proteins (transcription factors) that bind to particular DNA sequences. Without the transcription factors, RNA polymerase II cannot bind to a promoter. However, KNH polymerase II itself is not a transcription factor. The complexity of initiation may derive, in part, from the fact that eukaryotic DNA is in the form of chromatin, which is inaccessible to RNA polymerases. Many RNA polymerase II promoters have the following features ... 

Thyroid transcription factor-1 (TTF-1), a nuclear tissue-specific protein transcription factor, is found in thyroid and thyroid tumors regardless of histologic type (except anaplastic type), as well as in lung carcinomas including adenocarcinomas (75%), non-small cell carcinomas (63%), neuroendocrine and small cell carcinomas (>90%), and squamous cell carcinomas (10%).258-258 Selectively expressed during embryogenesis in the thyroid, the diencephalon of the brain, and in respiratory epithelium, TTF-1 binds to and activates factors for surfactant protein derived from Clara cells.255 TTF-1 is rarely seen in carcinomas outside of the lung or thyroid... 

Regulatory proteins (transcription factors) are involved in controlling gene expression in all cells. These regulatory proteins bind to specific DNA sequences and thereby activate or inhibit the transcription of genes (Transcription control). The effects of transcription factors are usually reversible and are often controlled by ligands or by interconversion. 

There is one complete twist of the helix every 10 base pairs, or 3.4 nm. This distance is referred to as the pitch of the helix. The surface of the heUx shows alternating major and minor grooves that follow the twist of the double-stranded molecule along its entire length. The major groove accommodates interactions with proteins (transcription factors see Chaps. 7 and 9) that recognize and bind to specific nucleotide sequences. 

To further expand the functionality of polypeptide hybrid hydrogels, aptamers that bind specifically to various small molecules and protein transcription factors (operator/promoter sequences) have been integrated in their network. Polyacrylamide main chains were branched with polynucleotide strands, which could be gelatinized by DNA base pairing with a second thrombin-bound polynucleotide strand ( cross-linker ). A third DNA strand that can form a duplex with the cross-linker strand was used to dissolve the hydrogel and to release the thrombin [100]. 

Initiation of transcription requires specific recognition of a promoter DNA sequence located upstream of the coding sequence of a gene by a RNA polymerase. This recognition is preceded by sequence-specific binding of one or more protein transcription factors to the promoter sequence. Additional proteins, which bind at or close to the promoter sequence, may upregulate transcription and are known as enhancers. 

Miller J, McLachlan AD, Klug A (1985) Repetitive zinc-binding domains in the protein transcription factor IIIA from Xenopus oocytes. EMBO J 4 1609-1614 Nemer M, Travaglini EC, Rondinello E, D Alonzo J (1984) Developmental regulation, induction and embryonic tissue specificity of sea urchin metallothionein gene expression. Dev Biol 102 471-482... 

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