PF3D7_1220900 heterochromatin protein 1

PfHP1 depletion induces gametocyte conversion. Distinction between 3D7/HP1OFF early gametocytes and arrested trophozoites by IFA (left) and proportion of Pfs16/KAHRP-positive parasites in 3D7/HP1ON and 3D7/HP1OFF (right). Values show the mean ± SD of three biological replicates (100 KAHRP-pos. iRBCs were scored per experiment). (D) a-Pfs16 IFA of a 3D7/HP1OFF parasite culture (Shield-1 removal at 4–12 hpi) at 32–40 hr postreinvasion (image taken at 40X magnification). The gametocyte hyperinduction phenotype is highlighted by the high proportion of Pfs16-positive stage I gametocytes among all DAPI-positive iRBCs. (C) Growth-arrested 3D7/HP1OFF parasites reenter mitotic proliferation after Shield-1 replenishment. dpi, days postreinvasion. PfHP1 depletion causes reversible cell-cycle arrest at the G1/S transition phase. Lower right panel: a-PfHP1/a-PfEMP1 (mAb 6H1) IFAs of 3D7/HP1ON and 3D7/HP1OFF parasites at 16–24 hpi in generation 2. PfEMP1 in 3D7/HP1OFF parasites at the single-cell level is hyperexpressed and correctly trafficked to the iRBC surface

Brancucci NM, Bertschi NL, Zhu L, Niederwieser I, Chin WH, Wampfler R, Freymond C, Rottmann M, Felger I, Bozdech Z, Voss TS. Heterochromatin protein 1 secures survival and transmission of malaria parasites. Cell Host Microbe. 2014 16(2):165-76.

Other associated proteins

PFID Formal Annotation
PF3D7_0406200 parasitophorous vacuole membrane protein s16; sexual stage-specific protein s16
PF3D7_1200600 erythrocyte membrane protein 1, PfEMP1