PDBsum entry 6a9c

Contractile protein

PDB id: 6a9c

Contents

Protein chains

66 a.a.

59 a.a.

Ligands

LYS-VAL-ALA-PRO-PRO-ILE-PRO-HIS-ARG

SO4 ×2

Waters ×54

PDB id:

6a9c

Name:

Contractile protein

Title:

Crystal structurE C-terminal sh3 domain of myosin ib from entamoeba histolytica bound to ehfp10(gef) peptide.

Structure:

Unconventional myosin ib. Chain: b, a. Fragment: sh3 domain. Engineered: yes. Peptide from rho guanine nucleotide exchange factor. Chain: e. Synonym: fp10(gef) peptide. Engineered: yes

Source:

Entamoeba histolytica. Organism_taxid: 5759. Gene: ehi_110810. Expressed in: escherichia coli. Expression_system_taxid: 562. Synthetic: yes. Organism_taxid: 5759

Resolution:

1.98Å R-factor: 0.203 R-free: 0.240

Authors:

G.Gautam,S.Gourinath

Key ref:

G.Gautam et al. (2019). EhFP10: A FYVE family GEF interacts with myosin IB to regulate cytoskeletal dynamics during endocytosis in Entamoeba histolytica. PLoS Pathog, 15, e1007573. PubMed id: 30779788 DOI: 10.1371/journal.ppat.1007573

Date:

13-Jul-18 Release date: 12-Jun-19

Protein chain

C4LUC7  (C4LUC7_ENTHI) -  Unconventional myosin IB from Entamoeba histolytica (strain ATCC 30459 / HM-1:IMSS / ABRM)

Seq: 1049 a.a.

Struc: 66 a.a.*

Protein chain

C4LUC7  (C4LUC7_ENTHI) -  Unconventional myosin IB from Entamoeba histolytica (strain ATCC 30459 / HM-1:IMSS / ABRM)

Seq: 1049 a.a.

Struc: 59 a.a.*

* PDB and UniProt seqs differ at 4 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chains B, A: E.C.?

DOI no: 10.1371/journal.ppat.1007573

PLoS Pathog 15:e1007573 (2019)

PubMed id: 30779788

EhFP10: A FYVE family GEF interacts with myosin IB to regulate cytoskeletal dynamics during endocytosis in Entamoeba histolytica.

G.Gautam, M.S.Ali, A.Bhattacharya, S.Gourinath.

ABSTRACT

Motility and phagocytosis are key processes that are involved in invasive amoebiasis disease caused by intestinal parasite Entamoeba histolytica. Previous studies have reported unconventional myosins to play significant role in membrane based motility as well as endocytic processes. EhMyosin IB is the only unconventional myosin present in E. histolytica, is thought to be involved in both of these processes. Here, we report an interaction between the SH3 domain of EhMyosin IB and c-terminal domain of EhFP10, a Rho guanine nucleotide exchange factor. EhFP10 was found to be confined to Entamoeba species only, and to contain a c-terminal domain that binds and bundles actin filaments. EhFP10 was observed to localize in the membrane ruffles, phagocytic and macropinocytic cups of E. histolytica trophozoites. It was also found in early pinosomes but not early phagosomes. A crystal structure of the c-terminal SH3 domain of EhMyosin IB (EhMySH3) in complex with an EhFP10 peptide and co-localization studies established the interaction of EhMySH3 with EhFP10. This interaction was shown to lead to inhibition of actin bundling activity and to thereby regulate actin dynamics during endocytosis. We hypothesize that unique domain architecture of EhFP10 might be compensating the absence of Wasp and related proteins in Entamoeba, which are known partners of myosin SH3 domains in other eukaryotes. Our findings also highlights the role of actin bundling during endocytosis.