Cover image

Cover Retrotransposon integrases (pink) are shown homing in on heterochromatin prior to inserting their cDNA (associated blue strands). Integrase chromodomains recognize histone tails that are methylated on lysine 9, which is characteristic of heterochromatin. In the background is an Arabidopsis leaf hair cell (trichome) expressing green fluorescent protein (GFP) fused to an integrase chromodomain. The eye-shaped nucleus is visible, and the punctate spots are domains of heterochromatin that accumulate the GFP fusion protein. (Cover illustration by Bang Wong, ClearScience, http://www.clearscience.info. [For details, see Gao et al., pp. 359–369.])