Euchromatin is that portion of the genome that is most active in gene transcription within the animal cell nucleus. It is in marked contrast to heterochromatin, which is the least active. And yet, either form of chromatin can be converted to the other, conversion to euchromatin being associated with new gene activation for RNA synthesis, and conversion to heterochromatin being associated with new gene repression for RNA synthesis.

Euchromatin synthesis of specific RNA species from selected gene loci is crucial in embryogenesis and cell differentiation, the immune response and the hormone response, organ regeneration and the neoplastic state. The Euchromatin Network is dedicated to current research on euchromatin and gene regulation.

Together with the Euchromatin Network, we are developing forums on all aspects of euchromatin, its composition, activity, control, and significance. We welcome your comments and suggestions in the design of these forums, and your participation in their on-going discussions.

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RNA comprises a series of ancient molecules involved in amino acid selection and activation, protein synthesis, and gene DNA expression. More recently, nuclear RNA species have been recognized for their roles in gene activation and gene silencing. Their flexible structure allows a myriad of configurations mediating positive and negative activity. They can be transferred into cells as naked RNA molecules, or as part of retrotransposons, or as nuclear transplants. They appear to be useful as therapeutic agents in early studies.

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5. Czihak G, "Evidence for inductive properties of the micromere RNA in sea urchin embryos",
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11. Frenster JH, "Oncogenes as Molecular Targets within Active Chromatin", in: AACR-NCI-EORTC International Conference: "Molecular Targets and Cancer Therapeutics: Discovery, Development, and Clinical Validation", Washington, DC, November 16-19, 1999, and Published in: Clinical Cancer Research, vol. 5, suppl. l, p. 3855s, (624), (November, 1999).

12. Frenster JH, "Activation of DNA Transcription within Repressed Chromatin", 14th John Innes Symposium, September 5-8, 2001.

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14. Frenster JH, "Yeast  RNA  Re-Programming  of  Already-Active  Mammalian Chromatin", RNA2002, p. 592, (June, 2002).

15. Lanz RB, Chua SS, Barron N, Söder BM, DeMayo F, and O'Malley BW, "Steroid Receptor RNA Activator Stimulates Proliferation as Well as Apoptosis In Vivo", Mol. Cell. Biol., vol. 23, no. 20, pp. 7163-7176 (October, 2003).

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23. Mathas S, Lietz A, Anagnostopoulos I, Hummel F, Wiesner B, Janz M, Jundt F, Hirsch B, Jöhrens-Leder K, Vornlocher H-P, Bommert K, Stein H, and Dörken B, "c-FLIP Mediates Resistance of Hodgkin/Reed-Sternberg Cells to Death Receptor–induced Apoptosis",  J. Exp. Med., vol. 199, no. 8, pp. 1041-1052 (April 19, 2004).

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26. Frenster JH, and Hovsepian JA, "Activator RNA Exchange during Interphase Chromatin Reprogramming".

27. Hovsepian JA, and Frenster JH, "Reprogramming as an Approach to Neoplasms".

28. Johnson SM, Grosshans H, Shingara J, Byrom M, Jarvis R, Cheng A, Labourier E, Reinert KL, Brown D, and Slack FJ, "RAS is regulated by the let-7 microRNA family". Cell 2005;120:635-647.

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34. Janz M, Hummel M, Truss M, Wollert-Wulf B, Mathas S, Johrens K, Hagemeier C, Bommert K, Stein H, Dorken B, and Bargou RC, "Classical Hodgkin lymphoma is characterized by high constitutive expression of activating transcription factor 3 (ATF3) which promotes viability of Hodgkin/Reed-Sternberg cells", Blood, vol. 107, no. 6, pp. 2536-2539 (March 15, 2006).

35. Kumar MS, Erkeland SJ, Pester RE, Chen CY, Ebert MS, Sharp PA, and  Jacks T.,
"Suppression of non-small cell lung tumor development by the let-7 microRNA family".
Published online on February 28, 2008: Proc. Natl. Acad. Sci. USA, 10.1073/pnas.0712321105

36. Frenster JH, and Hovsepian JA, "Models of  Embryonic RNA Initiating and Reverting Adult Neoplasms".

37. Bueno MJ, de Castro IP, de Cedrón MG, Santos J, Calin GA, Cigudosa JC, Croce CM, Fernández-Piqueras J and Malumbres M, "Genetic and Epigenetic Silencing of MicroRNA-203 Enhances ABL1 and BCR-ABL1 Oncogene Expression".
 
 

Further Topics in:  Euchromatin,  active DNA, and  RNA  ribo-regulators:

Reviews and Research:

Links to Euchromatin Activator RNA Reviews:
Links to Euchromatin Activator RNA Research:
Links to Ultrastructural Probes of DNase I-Sensitive Sites:
Links to RNA as a Therapeutic Agent:
Links to Hodgkin Lymphoma Immuno-Pathology:
Links to Activated T-Lymphocyte Immunotherapy:
Links to Medical Systems Biology:

"Ultrastructural Probes of Active DNA Sites, and the RNA Activators of DNA".

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