Cloning, Localization, and Functional Expression of Sodium Channel β1A Subunits
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Auxiliary beta1 subunits of voltage-gated sodium channels have been shown to be cell adhesion molecules of the Ig superfamily. Co-expression of alpha and beta1 subunits modulates channel gating as well as plasma membrane expression levels. We have cloned, sequenced, and expressed a splice variant of beta1, termed beta1A, that results from an apparent intron retention event. beta1 and beta1A are structurally homologous proteins with type I membrane topology; however, they contain little to no amino acid homology beyond the shared Ig loop region. beta1A mRNA expression is developmentally regulated in rat brain such that it is complementary to beta1. beta1A mRNA is expressed during embryonic development, and then its expression becomes undetectable after birth, concomitant with the onset of beta1 expression. In contrast, beta1A mRNA is expressed in adult adrenal gland and heart. Western blot analysis revealed beta1A protein expression in heart, skeletal muscle, and adrenal gland but not in adult brain or spinal cord. Immunocytochemical analysis of beta1A expression revealed selective expression in brain and spinal cord neurons, with high expression in heart and all dorsal root ganglia neurons. Co-expression of alphaIIA and beta1A subunits in Chinese hamster lung 1610 cells results in a 2.5-fold increase in sodium current density compared with cells expressing alphaIIA alone. This increase in current density reflected two effects of beta1A: 1) an increase in the proportion of cells expressing detectable sodium currents and 2) an increase in the level of functional sodium channels in expressing cells. [(3)H]Saxitoxin binding analysis revealed a 4-fold increase in B(max) with no change in K(D) in cells coexpressing alphaIIA and beta1A compared with cells expressing alphaIIA alone. beta1A-expressing cell lines also revealed subtle differences in sodium channel activation and inactivation. These effects of beta1A subunits on sodium channel function may be physiologically important events in the development of excitable cells.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it