Biology subjects

Wood, E. M.

Publications and source records attributed to Wood, E. M..

3 recordsLinked to original sources

bioRxiv2026

Hippocampal CA2 modulates trace fear conditioning through circuit-specific control of CA1

Forming associations between temporally separated events depends on pathways linking the CA1, the subiculum (SUB), and the entorhinal cortex. The degree to which this process requires the CA2, which shares extensive connectivity with these regions, remains unknown. Using trace fear conditioning (TFC), where mice learn to associate a tone and shock separated by a temporal gap, we showed that the dCA2 contributes to TFC. Interestingly, whereas chronic dCA2 inhibition decreased cue-associated freezing, acute dCA2[->]dCA1 projection inhibition increased freezing. Combined with differential effects on cFos expression, this suggests that global and projection-specific perturbations of the dCA2 have distinct effects on TFC and hippocampal activity states. Fiber photometry revealed that dCA2[->]dCA1 activity shifted from tone responsiveness during conditioning to expected shock activation during recall, consistent with learning-associated activity remodeling. Together, these findings identify the dCA2 as a contributor to TFC and implicate dCA2[->]dCA1 signaling in shaping fear expression across learning and recall.

neuroscience↗

bioRxiv2025

Response dynamics of discrete subiculum->retrosplenial cortex projections underlying trace fear conditioning

Associating events separated in time depends on the CA1, subiculum (SUB), and retrosplenial cortex (RSP). The degree to which their connectivity and underlying circuit mechanisms contribute to the association of such temporally discontiguous events is not known. Here we showed, using trace fear conditioning (TFC), wherein mice learn to associate tone and shock separated by a temporal trace, that molecularly distinct excitatory VGluT1+ and VGluT2+ SUB[->]RSP projections subserve the associative and temporal components of TFC. During trace memory formation, VGluT2+ SUB[->]RSP projections showed increased and decreased bulk calcium activity at tone and trace onset, respectively, an activity pattern that was reestablished during memory recall. Such pattern was not observed in CA subfields, suggesting that associative and temporal components of TFC are integrated at the SUB or SUB[->]RSP synapses before being presented to the RSP. Our findings establish a circuit mechanism for representing complex temporal information in episodic memory.

neuroscience↗

bioRxiv2020

Older mothers produce offspring with longer telomeres: a longitudinal within-parent analysis

As telomere length often predicts survival and lifespan, there is considerable interest in understanding the origins of inter-individual variation in telomere length. Transgenerational effects of parental age on offspring telomere length are thought to be a key source of variation, but the rarity of longitudinal studies that examine the telomeres of successive offspring born throughout the lives of parents leaves such parental age effects poorly understood. Here, we exploit telomere length measures of successive offspring produced throughout the long breeding tenures of parents in wild white-browed sparrow-weaver (Plocepasser mahali) societies, to isolate the effects of within-parent changes in age on offspring telomere lengths. Our analyses reveal the first evidence to date of a positive within-parent effect of advancing age on offspring telomere length: as individual mothers age they produce offspring with longer telomeres. We consider the potential for pre- and post-natal mechanisms to explain our findings. As telomere erosion predicts offspring mortality in this species, this positive parental age effect could significantly impact parent and offspring fitness. Our findings support the view that transgenerational effects of parental age can be an appreciable source of inter-individual variation in telomere length.

evolutionary biology↗