Iqy

y Steroid receptor y Steroid receptor

FIGURE 13-20 Schematic models illustrating how steroid antagonists (antihormones) might block the formation of a competent ligand-receptor-mediated transcription complex. (A) In this model, a pure antagonist interferes with the nuclear-cytoplasmic shuttling process, with the result that the receptor accumulates in the cytoplasm and is degraded. Abbreviations: HRE, hormone response element; hsp 90, heat shock protein 90; AH, antihormone. (B) In this model, the key point is that an antihormone (AH) does not induce a receptor conformational change that removes a surface repressor (R) function. Abbreviations: H, hormone; AH, antihormone; AF, activation function; R, repressor function; DNA, DNA-binding domain; "w- dimerization domain; N, amino terminus. Modified with permission from Tsai, M.-J., and O'Malley, B. W. (1994). Molecular mechanisms of actions of steroid/thyroid receptor superfamily members. Ann. Rev. Biochem. 63, 451-486.

Stimulated transcription

Blocked transcription

FIGURE 13-20 Schematic models illustrating how steroid antagonists (antihormones) might block the formation of a competent ligand-receptor-mediated transcription complex. (A) In this model, a pure antagonist interferes with the nuclear-cytoplasmic shuttling process, with the result that the receptor accumulates in the cytoplasm and is degraded. Abbreviations: HRE, hormone response element; hsp 90, heat shock protein 90; AH, antihormone. (B) In this model, the key point is that an antihormone (AH) does not induce a receptor conformational change that removes a surface repressor (R) function. Abbreviations: H, hormone; AH, antihormone; AF, activation function; R, repressor function; DNA, DNA-binding domain; "w- dimerization domain; N, amino terminus. Modified with permission from Tsai, M.-J., and O'Malley, B. W. (1994). Molecular mechanisms of actions of steroid/thyroid receptor superfamily members. Ann. Rev. Biochem. 63, 451-486.

TABLE 13-9 Relative Effectiveness of Various Contraceptive Methods

Contraceptive method

Number1" (millions)

Failures/100 Women Years"

Vasectomy of the male

Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

Get My Free Ebook


Post a comment