Nuclear transport¶
Moves molecular cargo between nucleoplasm and cytoplasm through nuclear pore complexes, with cargo-dependent passive or facilitated passage across a persistent nuclear envelope.
Core Idea¶
Nuclear transport, scoped here to nuclear-pore-mediated passage, moves molecular cargo between nucleoplasm and cytoplasm while the nuclear envelope remains a compartment boundary.[^ref-bc36b20386f0] Nuclear pore complexes provide cargo-dependent crossing pathways, with passive and facilitated modes that need different molecular explanations.[^ref-bc36b20386f0] Passive reporter macromolecules can equilibrate without nuclear transport receptors or GTP hydrolysis.[^ref-bc36b20386f0] The tested SUMO E1 import route instead uses nuclear localization signals and importin α/β,[^ref-7e1a37ec2edf] so that machinery should not be imposed on every transport instance.
Scope of Application¶
Use the relation for demonstrated NPC passage across a retained nuclear envelope:
- Passive equilibration: engineered GFP-fusion reporters in living yeast move between nuclear and cytoplasmic pools after controlled cytoplasmic photobleaching.[^ref-bc36b20386f0]
- Subunit import: tested Aos1 and Uba2 enter HeLa nuclei through an NLS/importin-dependent route.[^ref-7e1a37ec2edf]
- Complex import: assembled SUMO E1 holoenzyme can also undergo the tested facilitated import.[^ref-7e1a37ec2edf]
- Completed mRNP export: passage includes cytoplasmic release, while blocked release inside a pore is a diagnostic near miss.[^ref-9c317ddb7ba0]
Clarity¶
Identify the cargo and passage mode before assigning a required signal, receptor or energy coupling. A static nuclear localization image cannot by itself quantify import efficiency; Moutty's study therefore uses controlled import assays.[^ref-7e1a37ec2edf] In the tested mRNP system, pore entry could occur after NXF1 depletion even though cytoplasmic release failed.[^ref-9c317ddb7ba0] Location, pore engagement and completed transfer should consequently remain separate claims, rather than one undifferentiated statement that a molecule reached the nucleus or left it.
Manages Complexity¶
The family shares cargo, a persistent boundary, a pore pathway, cargo-dependent interaction and cross-compartment transfer. Those roles help distinguish the common crossing relation from route-specific molecular machinery without making passive exchange and receptor-mediated import identical. A missing receptor need not invalidate a passive case, whereas an unreleased cargo does not establish completed export. The summary helps choose the next question but cannot replace a particular pathway's evidence, its measurement timescale or the controls used to infer actual movement.
Abstract Reasoning¶
Select a perturbation that matches the claimed mode rather than applying one universal transport test. Molecular mass and permeability affect the passive reporter equilibration studied by Timney and colleagues.[^ref-bc36b20386f0] NLS mutations and importin-related interventions test the SUMO E1 facilitated route,[^ref-7e1a37ec2edf] while mRNP export blocks can distinguish engagement from release.[^ref-9c317ddb7ba0] A failure in one such experiment supports a dependence within that tested route, and does not prove that every nuclear cargo needs the same component or that static accumulation identifies a transport rate.
Knowledge Transfer¶
Yeast passive reporters and human SUMO E1 import replace cargo and molecular interaction while preserving passage across the nuclear envelope through NPCs.[ref-bc36b20386f0][ref-7e1a37ec2edf] Boundary is a prerequisite because scoped passage requires an inside/outside distinction and crossing conditions; nuclear transport adds cargo, NPC pathways and transfer. An organizational access gate can suggest comparative questions without importing the cellular machinery or the experiment's specific dependencies. Movement entirely within a nucleus, free mixing after envelope breakdown and unaddressed non-NPC routes therefore remain outside this entry's scope, even when the word nuclear is used.
Relationships to Other Abstractions¶
Current abstraction Nuclear transport Domain-specific
Parents (1) — more general patterns this builds on
-
Nuclear transport presupposes Boundary Prime
Scoped nuclear transport requires a persistent nucleus–cytoplasm boundary whose pore pathways regulate crossing.
Hierarchy path (1) — routes to 1 parentless root
- Nuclear transport → Boundary
Neighborhood in Abstraction Space¶
Nuclear transport sits in a sparse region of the domain-specific corpus (92nd percentile for distinctiveness): few abstractions share its structure, so a faithful description tends to retrieve it precisely.
Family — Molecular & Cellular Biology Mechanisms (16 abstractions)
Nearest neighbors
- Nuclear export signal — 0.82
- Biological pathway — 0.79
- Reuptake inhibitor — 0.78
- Mass transfer — 0.78
- Concerted Evolution — 0.78
Computed from structural-signature embeddings · 2026-10-17
References¶
[^ref-bc36b20386f0]: Benjamin L. Timney and coauthors. (2016). Simple rules for passive diffusion through the nuclear pore complex, Journal of Cell Biology 215(1), 57–76. Full original article consulted; Introduction and Results, Quantification of NPC permeability in vivo, Figure 1. Engineered yeast reporters support passive equilibration and a soft size-dependent barrier; the passive-mode inference is not a universal rate law for facilitated cargo. [^ref-7e1a37ec2edf]: Marie Christine Moutty, Volkan Sakin and Frauke Melchior. (2011). Importin α/β mediates nuclear import of individual SUMO E1 subunits and of the holo-enzyme, Molecular Biology of the Cell 22(5), 652–660. Full original article consulted; Results and Figures 2–5. The tested preparations are intact HeLa cells and import into nuclei of semipermeabilized HeLa cells; the findings establish this cargo's import pathway without a direct all-cell Ran-gradient measurement. [^ref-9c317ddb7ba0]: Rakefet Ben-Yishay and coauthors. (2019). Imaging within single NPCs reveals NXF1's role in mRNA export on the cytoplasmic side of the pore, Journal of Cell Biology 218(9), 2962–2981. Full original article consulted; Abstract, Results and Videos 3–4. The tested entry/release distinction concerns human mRNP export and does not directly test Ran independence across all cargo classes.