Abstract
We have isolated two DNA elements-Eh MRS1 and Eh MRS2-from
Entamoeba histolytica, which contain the eukaryotic consensus Scaffold/Matrix Attachment Region (S/MAR) bipartite recognition sequences. Both these sequences bind to high salt extractable nuclear proteins and insoluble nuclear matrix proteins in
E. histolytica HM1:IMSS, suggesting that the predicted S/MAR recognition sequences may indeed function as scaffold attachment regions in
E. histolytica. Sequence analysis shows that Eh MRS1 and Eh MRS2 contain internal tandem repeats ranging from units of 8–11
bp and are themselves present as independent arrays of tandemly repeating units of approximately 1100
bp each. Eh MRS1 and Eh MRS2 are localised on different chromosomes in
E. histolytica HM1:IMSS. Both Eh MRS1 and Eh MRS2 also code for small molecular weight RNAs of unknown function. Thus, two unique sequences-Eh MRS1 and Eh MRS2-demonstrate very similar properties, suggesting that they belong to a superfamily of genomic elements, which may function as scaffold or matrix attachment sites in
Entamoeba.
