[Frontiers in Bioscience 14, 3483-3495, January 1, 2009]
MLL histone methylases in gene expression, hormone signaling and cell cycle

Khairul I. Ansari, Bibhu P. Mishra, Subhrangsu S. Mandal

Gene Regulation and Disease Laboratory, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. MLL, histone methylation and gene expression
3.1. H3K4 methylation in yeast and its roles on transcription
3.2. MLLs are human histone H3 lysine 4 (H3K4) specific methyl-transferases
3.3. MLLs are present as multi protein complexes 3.4. MLL interacting proteins play critical roles in histone methylation and MLL target gene expression 3.5. MLLs are key regulators of Hox genes
3.6. MLLs interact with nuclear hormone receptors and regulate hormone dependent gene expression
3.7. MLLs and cell cycle regulation
3.7.1. MLLs interact with cell cycle regulatory proteins
3.7.2. MLL target Hox genes in cell cycle regulation
4. Discussion
5. Acknowledgements
6. References

1. ABSTRACT

Histone methyl-transferases (HMTs) are key enzymes that post-translationally methylate nuclear histone proteins and play critical roles in gene expression, epigenetic regulation and diseases in eukaryotic organisms. Mixed lineage leukemias (MLLs) are human HMTs that specifically methylate histone H3 at lyisine-4 and regulate gene activation. MLLs are also well known to be rearranged often in acute myeloid and lymphoid leukemias. Human encodes several MLLs that have similar enzymatic activities but diverse functions. Herein, we have reviewed the recent advances in understanding the diverse functions of MLL family of HMTs in gene regulation, hormone signaling and cell cycle regulation in human.