**16. References**

Anilkumar, P., Vidya, S.K. & Thampan, R.V. (2010) Goat endometrial heat shock protein –90 (Hsp-90). Development of an expedient method for its purification and observations on its intracellular movement. *Protein Expression Purific*.71:49-53.

The assumption is that nERII binding to subunits of RNA polymerase I, followed by nERII mediated tyrosine phosphorylation of those subunits results in the dissociation of the subunits from the enzyme along with the rRNA, remaining bound to nERII. The rRNAnERII-RNA polymerase I subunit complex is shown here as forming an integral part of the

I wish to speculate here that the subunits dissociated form the RNA polymerases following phosphorylation by nERII could continue their association with nERII and find their involvement in splicing reactions, nucleocytoplasmic transport of RNA and eventually, in translation. If this assumption is correct, future studies on ribosomal subunits should be able to confirm the presence of RNA polymerase I and III subunits in 40S ribosomes. It should also be possible to confirm whether the RNA polymerase II subunits are present in

1. Discussions exclusively on the classical estrogen receptors, ERα and ERβ will serve to uncover only limited information on the role of the receptors in regulating gene

2. There is a distinct possibility that naER-E-RAF heterodimer has a parallel role to play in

3. nERII is undoubtedly the estrogen receptor that mediates post transcriptional events in

4. The nERII-mediated events are related to gene expression protocols influenced by all 4

5. E-RAF targets both the nucleus and the mitochondria. Free E-RAF, progesteronebound E-RAF and cholesterol bound E-RAF encounter distinct genes that are under regulatory influence. It might function as cholesterol transporter to the mitochondria and facilitate mitochondrial steroidogenesis leading to the production of progesterone. This is, in all possibility, a mechanism projected to take place during

6. The possibility exists that there is an "external"regulator of E-RAF gene expression and also that this regulatory agent is involved in the control of E-RAF gene expression in the

7. The possibility for a role for E-RAF in the progression of mammary cancer cannot be ruled out. Studies to be held in the near future are bound to enlighten this possibility.

I wish to acknowledge with gratitude and deep appreciation the contributions of my research students, both past and present. Their observations have made a profound impact

Anilkumar, P., Vidya, S.K. & Thampan, R.V. (2010) Goat endometrial heat shock protein –90

(Hsp-90). Development of an expedient method for its purification and observations on its intracellular movement. *Protein Expression Purific*.71:49-53.

regulating transcriptional events as has been proposed for ERα and ERβ.

**14. General conclusions and hypothetical possibilities** 

gene expression in estrogen target cells.

on my search into the mysteries of estrogen action.

forms of nuclear RNA polymerases.

40S subunit of the ribosome.

spliceosomes.

expression.

pregnancy.

pregnant uterus.

**15. Acknowledgement** 

**16. References** 


Evolving Trends in Estrogen Receptor Biology 81

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**Part 2** 

**Pathophysiology of Steroid Hormones** 

