GLT-1 (NCU01633) is a multipass major-facilitator-family glucose transporter in Neurospora crassa. It supports low-affinity, high-capacity glucose uptake and is prominent under glucose-replete conditions; high-affinity HGT-1/HGT-2 transporters can compensate for its deletion. Tagged-protein imaging and uptake experiments support function at the cell boundary. GLT-1 has been assigned to the historical system-I diffusion pathway, while its precise energetic coupling requires distinction from the directly measured glucose kinetics.
Summary: Protein-specific glucose uptake is established, but the degree to which GLT-1 excludes proton coupling remains unresolved.
Reason: PMID:28115989 assigns GLT-1 to historical low-affinity system I and describes system I as a glucose diffusion system. However, its GLT-1 measurements concern radioglucose kinetics, expression, complementation and localization; low affinity alone does not establish proton independence. The current PTN000627328 symporter IBD is ancestral to the exact target leaf, with no recovered loss assertion. The existing Falcon report also distinguishes the direct glucose evidence from less direct mechanism assignment. A focused question is queued to reconcile historical whole-cell energetics with molecular identification. Do not reject the inherited coupling merely because a target proton-flux experiment is absent.
Propagation Review
Root cause:UNRESOLVED
Sources checked:
PANTHER:PTN000627328 · PTN000627328 UNRESOLVED
Actual ancestry verified; historical system-I mechanistic inference requires reconciliation with the target-specific assays.
Summary: The broad membrane or carbohydrate-transport term correctly includes GLT-1-mediated glucose uptake.
Reason: Target expression/complementation and radiolabeled-sugar uptake establish glucose transport, and the multipass MFS architecture supports membrane localization. PMID:28115989 measures low-affinity glucose uptake and includes tagged-protein imaging in yeast and Neurospora. More specific glucose and plasma-membrane descriptions do not make the broader existing assertions false. The three IBA terms arise at PTN000627328, an actual ancestor of target leaf PTN002362095.
Propagation Review
Root cause:NO FAILURE CORE
Sources checked:
PANTHER:PTN000627328 · PTN000627328 SUPPORTS TRANSFER
Actual target descends from the membrane/carbohydrate-transport IBD; direct glucose uptake supports the broad inference.
Summary: The broad membrane or carbohydrate-transport term correctly includes GLT-1-mediated glucose uptake.
Reason: Target expression/complementation and radiolabeled-sugar uptake establish glucose transport, and the multipass MFS architecture supports membrane localization. PMID:28115989 measures low-affinity glucose uptake and includes tagged-protein imaging in yeast and Neurospora. More specific glucose and plasma-membrane descriptions do not make the broader existing assertions false. The three IBA terms arise at PTN000627328, an actual ancestor of target leaf PTN002362095.
Propagation Review
Root cause:NO FAILURE CORE
Sources checked:
PANTHER:PTN000627328 · PTN000627328 SUPPORTS TRANSFER
Actual target descends from the membrane/carbohydrate-transport IBD; direct glucose uptake supports the broad inference.
Summary: The broad membrane or carbohydrate-transport term correctly includes GLT-1-mediated glucose uptake.
Reason: Target expression/complementation and radiolabeled-sugar uptake establish glucose transport, and the multipass MFS architecture supports membrane localization. PMID:28115989 measures low-affinity glucose uptake and includes tagged-protein imaging in yeast and Neurospora. More specific glucose and plasma-membrane descriptions do not make the broader existing assertions false. The three IBA terms arise at PTN000627328, an actual ancestor of target leaf PTN002362095.
Summary: The broad membrane or carbohydrate-transport term correctly includes GLT-1-mediated glucose uptake.
Reason: Target expression/complementation and radiolabeled-sugar uptake establish glucose transport, and the multipass MFS architecture supports membrane localization. PMID:28115989 measures low-affinity glucose uptake and includes tagged-protein imaging in yeast and Neurospora. More specific glucose and plasma-membrane descriptions do not make the broader existing assertions false. The three IBA terms arise at PTN000627328, an actual ancestor of target leaf PTN002362095.
Summary: The broad membrane or carbohydrate-transport term correctly includes GLT-1-mediated glucose uptake.
Reason: Target expression/complementation and radiolabeled-sugar uptake establish glucose transport, and the multipass MFS architecture supports membrane localization. PMID:28115989 measures low-affinity glucose uptake and includes tagged-protein imaging in yeast and Neurospora. More specific glucose and plasma-membrane descriptions do not make the broader existing assertions false. The three IBA terms arise at PTN000627328, an actual ancestor of target leaf PTN002362095.
Summary: The broad membrane or carbohydrate-transport term correctly includes GLT-1-mediated glucose uptake.
Reason: Target expression/complementation and radiolabeled-sugar uptake establish glucose transport, and the multipass MFS architecture supports membrane localization. PMID:28115989 measures low-affinity glucose uptake and includes tagged-protein imaging in yeast and Neurospora. More specific glucose and plasma-membrane descriptions do not make the broader existing assertions false. The three IBA terms arise at PTN000627328, an actual ancestor of target leaf PTN002362095.
Summary: Protein-specific glucose uptake is established, but the degree to which GLT-1 excludes proton coupling remains unresolved.
Reason: PMID:28115989 assigns GLT-1 to historical low-affinity system I and describes system I as a glucose diffusion system. However, its GLT-1 measurements concern radioglucose kinetics, expression, complementation and localization; low affinity alone does not establish proton independence. The current PTN000627328 symporter IBD is ancestral to the exact target leaf, with no recovered loss assertion. The existing Falcon report also distinguishes the direct glucose evidence from less direct mechanism assignment. A focused question is queued to reconcile historical whole-cell energetics with molecular identification. Do not reject the inherited coupling merely because a target proton-flux experiment is absent.
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.
Review rationale: Heterologous radiotracer uptake and growth complementation establish D-glucose transport by GLT-1 (PMID:24581151); the later kinetic study identifies it as the low-affinity glucose transporter. Generic transmembrane transporter activity is correct but less precise than the supported D-glucose activity. This judgment concerns solute transport, not proton coupling.
Supporting Evidence:
PMID:24581151: "We conclude that NCU01633 is a D-glucose transporter of N. crassa, which was therefore named as D-glucose transporter 1 (GLT-1)."
Review rationale: The MFS membrane-spanning architecture and uptake of extracellular glucose support membrane residence, with plasma membrane inferred from the demonstrated physiological transport route. Membrane is therefore less precise than the supported plasma-membrane assignment. The specific compartment is a functional inference, not a claimed native imaging result.
Supporting Evidence:
PMID:24581151: "We conclude that NCU01633 is a D-glucose transporter of N. crassa, which was therefore named as D-glucose transporter 1 (GLT-1)."