Renshaw Cells and Ia Inhibitory Interneurons Are Generated at Different Times from p1 Progenitors and Differentiate Shortly after Exiting the Cell Cycle
Bibliographic record
Abstract
Spinal interneurons modulating motor output are highly diverse but surprisingly arise from just a few embryonic subgroups. The principles governing their development, diversification, and integration into spinal circuits are unknown. This study focuses on the differentiation of adult Renshaw cells (RCs) and Ia inhibitory interneurons (IaINs), two subclasses that respectively mediate recurrent and reciprocal inhibition of motoneurons from embryonic V1 interneurons (V1-INs). V1-INs originate from p1 progenitors and, after they become postmitotic, specifically express the transcription factor engrailed-1, a property that permits genetic labeling of V1 lineages from embryo to adult. RCs and IaINs are V1 derived, but differ in morphology, location, calcium-binding protein expression, synaptic connectivity, and function. These differences are already present in neonates, and in this study we show that their differentiation starts in the early embryo. Using 5'-bromodeoxyuridine birth dating we established that mouse V1-INs can be divided into early (E9.5-E10.5) and late (E11.5-E12.5) groups generated from the p1 domain (where E is embryonic day). The early group upregulates calbindin expression soon after becoming postmitotic and includes RCs, which express the transcription factor MafB during early differentiation and maintain calbindin expression throughout life. The late group includes IaINs, are calbindin-negative, and express FoxP2 at the start of differentiation. Moreover, developing RCs follow a characteristic circumferential migratory route that places them in unique relationship with motor axons with whom they later synaptically interact. We conclude that the fate of these V1-IN subclasses is determined before synaptogenesis and circuit formation by a process that includes differences in neurogenesis time, transcription factor expression, and migratory pathways.
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.
How this classification was reachedexpand
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 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".