steriod hormone signaling

signaling mechanism

1. INDIRA GANDHI NATIONAL TRIBAL UNIVERSITY DEPARTMENT OF ZOOLOGY PRESENTED BY, TARAKESWAR PATEL, ENROLL NO-1801170013 M.SC 2 ND SEMISTER GUIDED BY, M.SC 2 ND SEMESTER STUDENT

2. STEROID HORMONE SIGNALING 2 TOPIC

3. STEROID HORMONE SIGNALING- C ONTAINS: WHAT IS STEROID ? WHAT IS STEROID HORMONE ? AND TYPE. (ONLY BASIC) WHAT IS SIGNALING ?AND TYPE. WHAT IS STEROID SIGNALING ?AND TRANSPORT WHAT IS GENOMIC PATHWAYS ? WHAT IS NON GENOMIC PATHWAYS DISSCUSSION 3

4. 1.WHAT IS STEROID ? A steroid is a biologically active compound with four rings arrange in specific molecular configuration. The steroid core structure is composed of seventeen carbon atoms bonded in four fused ring( cyclohaxane ring-A,B,C ) and one five member ring( cyclopantane ring-D ). Steroid vary by the functional groups attached to this four ring core and by the oxidation state of the ring. 4

5. 2.WHAT IS STEROID HORMONE ? AND TYPE A steroid hormone is a steroid that acts as a hormone i.e they are secreted from glands of the body . Steroid hormones can be grouped in to two classes – Corticosteroid -typically made in adrenal cortex and they have two main class glucocorticoids and mineralocorticoids , which are widely use in physiological process, including stress response , immune response and regulation of inflammation , behavior and major metabolism process. Sex steroid -also knows as gonadocorticoid which interact with androgen , estrogen and progestogen receptors. 5

6. 3) How they synthesize ? Synthesis - The natural steroid hormones are generally synthesized from the cholesterol in adrenal gland and gonads i.e. They are synthesized in the testes , the ovaries . 6

7. 3.What is signaling ? and type Signaling is part of the communication process that governs basic activities and coordinates all cell actions. It mainly required for homeostasis and hormonal contro l and growth and development . Based upon the receptor present for signaling they are cell surface signaling and steroid signaling . 7

8. 4.WHAT IS STEROID HORMONE SIGNALING? AND TRANSPORT When the signal transduction carried out by steroid hormone that’s called the steroid hormone signaling . During the study of the signaling mechanism the transport of these hormone should be known. Transport- Steroid hormones are transported through the blood by being bound to the carrier proteins which are the serum proteins that bind them and increase the hormones solubility in water. Most study say that hormones can affect cell when are not bound by the serum protein .( 99 % steroid are protein bounded but only 1% that are free responsible for the transmission of signal ). In order to perform their work they free them selves from blood protein and passively cross the cell membrane and bind to the cytosolic receptor or nuclear receptor. The idea is known as free hormone hypothesis . 8

9. MECHANISM- There are many different mechanism through which steroid hormones affect their target cell. All of these pathways can be classified in to genomic effect, or a non genomic effect. Genomic pathways are slow and results in altering transcriptional levels of p roteins in the cell, non genomic pathways are much faster 9

10. 10 What is genomic pathways? In this pathways, the free steroid hormones first pass through the cell membrane by simple diffusion as they are fat soluble . In the cytoplasm they does not under goes any modification and bind to a specific steroid hormone receptor also known as nuclear receptor which is a large metalloprotein belongs to zinc finger protein super family . Each steroid hormone has its own specific intracellular receptor . Before binding to hormone ,these steroid hormone receptor exist as monomers and they are bind to heat shock proteins and they are incapable of binding with DNA. When the receptor bind with ligand (hormone) the hsp dissociate from the receptor because the ligand have a high affinity binding with receptor as compare to hsp. After that steroid hormone complex translocate into the nucleus of the cell.

11. 11 TYPE-1( ANDROGEN,ESTROGEN,GLUCOCORTICOID,PROGETERONE RECEPTOR

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14. 14 Then the steroid complex dimerised and bind to the specific site of the DNA called hormone receptor elements . After binding these complex activate coactivators followed by activation of RNA polymerase leads to transcription and the mRNA translocated to the cytoplasm and upon translation specific protein are formed leads to cellular response. Ex-estrogen steroid signaling etc. TYPE -2 (THYROID HORMONE RECEPTOR)

15. 15 What is non-genomic pathways? The non genomic pathway mediated by some kind of steroid hormone receptor found in plasma membran e. The evidence regarding non genomic pathway shown by ion channels , transporters , G- protein coupled receptor, and membrane fluidity affected by steroid hormones.

16. 16 REFERANCE- ENDOCRINOLOGY (MAC E HADLEY) CELL BIOLOGY (COOPER) CELL AND MOLECULAR BIOLOGY ( AJOYA PAUL) STEROID HORMONE SIGNALING PAPER (NCBI) ESTROGEN SIGNALING THANK YOU

17. 17 DISCUSSION YOU MAY ASK QUESTIONS ?