Ch12.3 - Steroid hormones alter gene expression by A....

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Steroid hormones alter gene expression by A. activating their receptors, making them capable of binding hormone response elements (HREs) in DNA. B. having hormone response elements (HREs) that bind DNA. C. activating their receptors, making their hormone response elements (HREs) capable of binding DNA. D. binding hormone response elements (HREs) in DNA. Regulation of gene expression in eukaryotes differs from bacteria in several ways: 1. Access to eukaryotic promoters is generally restricted by the structure of chromatin 2. Activation of transcription is associated with changes in chromatin structure (chromatin remodeling) 3. Positive regulation predominates in eukaryotes 4. Transcription and translation are spatially separated General components required for transcription activation in eukaryotes: Binding of RNA pol II to a promoter usually requires (1) basal transcription factors (see Fig. 26-9), (2) chromatin modiFcation and remodeling enzymes (next slide), (3) transcriptional activators which bind specic DNA sequences in promoter and (4) coactivators (e.g. Mediator ) which act as intermediaries between activator proteins and PIC. Regulation of transcription of GAL genes by Ga14p, Gal80p and Gal3p Gal80p forms a complex with Gal4p, preventing Gal4p from activating transcription. What happens when galactose is present (and [glucose] )? Fig. 12-40 Steroid (and related) hormones regulate gene expression by binding to nuclear receptors Bicoid and Nanos regulate gene expression to establish ant/post ends Bicoid- transcriptional activator and translational repressor (anterior) Nanos- translational repressor (posterior) Caudal- transcriptional activator (development of posterior) Hunchback- transcriptional regulator (development of anterior) Pumilio- translational repressor (requires nanos to function; represses hunchback mRNA) Development of which end is caudal involved in? Chapter 12 Regulation of Cell Cycle, Cancer and Apoptosis Which of the following leads to a block in cell division? A. phosphorylation of the retinoblastoma protein (pRb) B. activation of cyclin E-CDK2 C. transcription of p21 D. activation of the transcription factor E2F The eukaryotic cell cycle Regulation of the eukaryotic cell cycle by cyclin-CDKs Cyclin-CDKs are protein kinases that are heterodimers with a regulatory subunit, cyclin , and a catalytic subunit, cyclin- dependent protein kinase (CDK). In the absence of cyclin, CDKs are inactive....
View Full Document

This note was uploaded on 09/21/2010 for the course CH 53380 taught by Professor Raymond during the Spring '10 term at University of Texas at Austin.

Page1 / 42

Ch12.3 - Steroid hormones alter gene expression by A....

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online