Hmt-1 is an ABCB6-family membrane transporter that couples ATP hydrolysis to solute translocation. The Drosophila protein confers cadmium tolerance and targets the vacuolar membrane when expressed in fission yeast, without requiring cadmium-phytochelatin transport. Conserved ABCB6-family properties support heme/porphyrin handling, while the physiological transported metal complex and the endogenous fly compartment remain incompletely resolved.
Summary: The specific Golgi membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific Golgi membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The transporter nucleotide-binding cassette uses ATP in the conserved ABC transport cycle.
Reason: The transporter nucleotide-binding cassette uses ATP in the conserved ABC transport cycle. ATP binding is more informative than generic nucleotide binding.
Summary: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain.
Reason: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain. Conserved ATP-powered transmembrane transport is supported by its diagnostic architecture and functional complementation of a cognate transporter mutant. The coupling mechanism is established for ABCB6-family structures; the fly assay does not identify every transported solute.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
Summary: The specific extracellular region assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific extracellular region assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific mitochondrial outer membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific mitochondrial outer membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific lysosomal membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific lysosomal membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The Drosophila protein complements cadmium sensitivity in fission-yeast hmt-1 mutants and localizes to their vacuolar membrane.
Reason: The Drosophila protein complements cadmium sensitivity in fission-yeast hmt-1 mutants and localizes to their vacuolar membrane. This establishes a conserved heavy-metal-tolerance role and vacuolar targeting in a heterologous assay; it does not demonstrate cadmium-phytochelatin transport or an endogenous fly compartment.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
IDA PMID:19001374 Drosophila ABC transporter, DmHMT-1, confers tolerance to ca...
ACCEPT
Summary: The Drosophila protein complements cadmium sensitivity in fission-yeast hmt-1 mutants and localizes to their vacuolar membrane.
Reason: The Drosophila protein complements cadmium sensitivity in fission-yeast hmt-1 mutants and localizes to their vacuolar membrane. This establishes a conserved heavy-metal-tolerance role and vacuolar targeting in a heterologous assay; it does not demonstrate cadmium-phytochelatin transport or an endogenous fly compartment.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific endoplasmic reticulum membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific endoplasmic reticulum membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific plasma membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific plasma membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific endosome membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific endosome membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability.
Reason: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability. Human ABCB6 binds hemin in a substrate-resolved structure, and the target retains the diagnostic ABCB6 architecture and a curated ancestral assignment. This is a justified family transfer, but the relative physiological contribution of heme transport versus metal detoxification in the fly is unresolved.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Summary: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability.
Reason: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability. Human ABCB6 binds hemin in a substrate-resolved structure, and the target retains the diagnostic ABCB6 architecture and a curated ancestral assignment. This is a justified family transfer, but the relative physiological contribution of heme transport versus metal detoxification in the fly is unresolved.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Summary: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability.
Reason: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability. Human ABCB6 binds hemin in a substrate-resolved structure, and the target retains the diagnostic ABCB6 architecture and a curated ancestral assignment. This is a justified family transfer, but the relative physiological contribution of heme transport versus metal detoxification in the fly is unresolved.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Summary: Membrane residence is supported by the multi-pass ABC transporter architecture and vacuolar localization of expressed DmHMT-1.
Reason: Membrane residence is supported by the multi-pass ABC transporter architecture and vacuolar localization of expressed DmHMT-1. Vacuolar membrane is the experimentally resolved compartment, with the qualification that localization was measured in fission yeast.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain.
Reason: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain. Conserved ATP-powered transmembrane transport is supported by its diagnostic architecture and functional complementation of a cognate transporter mutant. The coupling mechanism is established for ABCB6-family structures; the fly assay does not identify every transported solute.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
Summary: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability.
Reason: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability. Human ABCB6 binds hemin in a substrate-resolved structure, and the target retains the diagnostic ABCB6 architecture and a curated ancestral assignment. This is a justified family transfer, but the relative physiological contribution of heme transport versus metal detoxification in the fly is unresolved.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Summary: The specific early endosome membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific early endosome membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific late endosome membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific late endosome membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: The specific multivesicular body membrane assignment is not resolved by the available DmHMT-1 experiment.
Reason: The specific multivesicular body membrane assignment is not resolved by the available DmHMT-1 experiment. The target protein localizes to a vacuolar membrane when expressed in fission yeast; this does not distinguish the many additional compartments assigned through automated location mappings. A target-resolved localization study or conserved targeting determinant for this compartment is missing, so this assignment is not promoted to a core site of action.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability.
Reason: Heme recognition and transport are supported as a conserved ABCB6-subfamily capability. Human ABCB6 binds hemin in a substrate-resolved structure, and the target retains the diagnostic ABCB6 architecture and a curated ancestral assignment. This is a justified family transfer, but the relative physiological contribution of heme transport versus metal detoxification in the fly is unresolved.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Summary: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain.
Reason: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain. Conserved ATP-powered transmembrane transport is supported by its diagnostic architecture and functional complementation of a cognate transporter mutant. The coupling mechanism is established for ABCB6-family structures; the fly assay does not identify every transported solute.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
Summary: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain.
Reason: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain. Conserved ATP-powered transmembrane transport is supported by its diagnostic architecture and functional complementation of a cognate transporter mutant. The coupling mechanism is established for ABCB6-family structures; the fly assay does not identify every transported solute.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
IGI PMID:19001374 Drosophila ABC transporter, DmHMT-1, confers tolerance to ca...
ACCEPT
Summary: The Drosophila protein complements cadmium sensitivity in fission-yeast hmt-1 mutants and localizes to their vacuolar membrane.
Reason: The Drosophila protein complements cadmium sensitivity in fission-yeast hmt-1 mutants and localizes to their vacuolar membrane. This establishes a conserved heavy-metal-tolerance role and vacuolar targeting in a heterologous assay; it does not demonstrate cadmium-phytochelatin transport or an endogenous fly compartment.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
Summary: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain.
Reason: Hmt-1 is a membrane ABCB6/HMT-1-family transporter with an ABC nucleotide-binding domain. Conserved ATP-powered transmembrane transport is supported by its diagnostic architecture and functional complementation of a cognate transporter mutant. The coupling mechanism is established for ABCB6-family structures; the fly assay does not identify every transported solute.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively.
Core Functions
ATP-powered membrane transport supports cellular cadmium detoxification; the precise metal-containing substrate remains unresolved.
heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR032410; ABCB6_N.
file:DROME/Hmt-1/Hmt-1-uniprot.txt
DR InterPro; IPR003439; ABC_transporter-like_ATP-bd.
These computational predictions are reviewed separately from the GOA annotation set used for this review. The assessments below are from this project and do not constitute official GO annotations or endorsement by GO/UniProt. They are not included in the existing annotation review above.
LSP — Less precise than existing annotation Review score: 2/2
Prediction method: ProtNLM2 · Version: UniProt API snapshot 2026-09-08
Review rationale: ABC-type transport is supported by the target ABCB6 architecture and functional rescue of the fission-yeast hmt-1 cadmium-sensitivity phenotype. The existing ABC-type heme transporter activity is more specific and has a justified ABCB6-family basis in hemin-bound structures, although the relative physiological substrate use in the fly remains unresolved. The broad prediction is biologically supported independently of the many unverified compartment assignments.
Supporting Evidence:
PMID:19001374: "heterologously expressed DmHMT-1 suppresses the Cd2+ hypersensitivity of S. pombe hmt-1 mutants and localizes to the vacuolar membrane but does not transport Cd.PC complexes."
PMID:35950458: "Here we report the cryo-electron microscopy (cryo-EM) structures of human ABCB6 with its substrates, coproporphyrin III (CPIII) and hemin, at 3.5 and 3.7 Å resolution, respectively."