Thyroid Hormone non-genomic TH diseases

Question 1

what are the nongenomic characteristics of thyroid hormone?

Answer 1

• no nuclear receptors
• rapid timing
• all forms of TH
• small amplitude
• signal transduction

Question 2

what are the genomic characteristics of thyroid hormone?

Answer 2

• has nuclear receptors
• slow enough timing for transcription
• t3 only
• huge amplitude
• no signal transduction

Question 3

what are the TH nongenomic effects?

Answer 3

rapid cellular responses to thyroid hormone that do not involve nuclear thyroid hormone receptor and transcription

Question 4

what examples of membrane receptors are involved in TH nongenomic effecrts?

Answer 4

calmodulin, protein kinase, integrins

Question 5

what are some rapid intracellular effects of TH nongenomic effects?

Answer 5

ion flux, mito activity (especially in the liver), glucose and amino acid uptake, actin polymerization, muscle contraction and pseudopod formation

Question 6

how do t4 and rt3 contribute to cellular processes?

Answer 6

(not t3) promote actin polymerization in rat brain cells, which is required for proper migration during development

Question 7

what is the role of integrins in TH nongenomic effects?

Answer 7

are receptors that mediate attachment between a cell and other cells or the extracellular matrix

Question 8

how do TH nongenomic and genomic paths cooperate together?

Answer 8

• t3 enters cell by specific transporter and acts in nucleus via TR
• t3 acts directly on ion channels at membrane

Question 9

how does TH affect TR in the nucleus?

Answer 9

through phosphorylation cascades, when TR is phosphorylated, it is activated, and co-repressor proteins dissociated

Question 10

what are examples of kinases involved in the crosstalk between TH nongenomic and genomic paths?

Answer 10

CDK - cyclin dependent kinase
MAPK - mitogen activated protein kinase