Articles

We investigated how targeted reactivation of cortical memory engrams during sleep influences systems consolidation of contextual fear memory. Using a mouse model of contextual fear conditioning (CFC), we tagged retrosplenial cortex (RSC) neurons activated during learning with channelrhodopsin-2 (ChR2) via a c-Fos-based TRAP system. Twenty-four hours post-training, animals received optogenetic stimulation of these RSC engram cells selectively during non-rapid eye movement (NREM) sleep or REM sleep. Immediately after, hippocampal activity was transiently blocked (muscimol infusion) to test hippocampal dependence. We found that NREM-specific reactivation of RSC engrams preserved contextual fear recall despite hippocampal inactivation, whereas REM stimulation or no stimulation failed to rescue memory. These results indicate that engram reactivation during NREM accelerates the transfer of memory to cortical storage. We present high-level diagrams of experimental workflow and results, and report a timeline of revisions. Abbreviations and keywords are provided. This comprehensive revision addresses all reviewer comments and renders the manuscript submission-ready.

Neurodegeneration and aging are pressing issues with significant personal, economic, ethical, and social consequences. However, the underlying biological mechanisms of these conditions remain largely unknown, making the development of effective treatments challenging. The difficulty in early detection and diagnosis of neurodegenerative diseases further compounds the issue. Recent advancements in genetics, genomics, and brain imaging technology hold great promise for improving our understanding of neurodegeneration and aging, as well as the development of personalized medicine and new drugs and therapies. Addressing these challenges will require a multi-disciplinary and collaborative approach from researchers in various fields. This Special Issue offers valuable insights and perspectives on this critical area of research, which can help advance our understanding and improve the health and well-being of our aging population.

One of the current issues facing humanity is ensuring sustained global food security in the face of devastating effects of climate change; this challenge is particularly pressing on the African continent. Here, I present an opinion piece identifying local animal genetic resources as "African leverage point" that provide the highest chances to cushion rural fork to climate change, enhance environmental sustainability and food security in Africa. When it comes to boosting food production, coping with climate change, or bolstering the delivery of a wide range of ecosystem services, I believe that African animal genetic resources are essential alternatives for the sustainable growth of the livestock industry and its contribution to food security. Africa needs to address the support and development of indigenous animal genetic resources in order to meet the basic food needs of more than 1 billion people, address numerous environmental issues with continental implications, and focus on more effective and resilient food systems with the greatest impact on food security. The indigenous animal resources diversity and support actions to this unique group could provide a boost in protein that is lacking to constitute healthy diets in Africa. The priorities of nonprofit organizations, foundations, governments, citizens' groups, and companies can be influenced by this leverage point in the African food system. Due to continuous food insecurity, which appears to be becoming worse with climate change and makes it even harder to accomplish the SDGs on the continent, Africa has paid a hefty price for being misled about the worth of its own animal genetic resources. To the contrary, it is highly improbable that a strategy to improve food security and rural livelihoods that undermines the utilization of indigenous animal genetic resources will be viable in long-term. If Africa makes an effort, is committed, and fully commits resources to putting indigenous animal genetic resources at the forefront of combating food insecurity and accelerating the achievement of SDGs, it can achieve more under the adverse prevailing climate change induce environmental conditions. Our personal opinion is that we would not have had the ongoing food problems, even in the face of climate change, if Africa had over the years implemented the necessary mechanisms to develop and promote local animal genetic resources. What lies ahead in terms of climate change effect on food security in Africa is anyone's guess – but whatever it is, promoting continental adapted indigenous animal genetic resources portfolio is ready to handle it. Development and promotion of African animal genetic resources should be part of a continental strategy to transform smallholder animal production by 2050, in line with the goals of achieving the SGDs, to improve rural household food security, and bringing rural economy prosperity, resilience, sustainability, and all other desired animal related food outcomes for rural healthy diets. African animal genetic resources are the most important but underutilized resource to address the issue of ongoing food insecurity. The responsible use of local animal genetic resources through climate smart animal husbandry practices also contributes to food security, rural development and increased employment opportunities. African genetic improvement programs involving indigenous animal genetic resources must be considered as regards to local agriculture and livestock development aspirations, appropriateness to local reality and livelihood security, as well as environmental friendliness. Animal agriculture will fill in the enormous gaps in the continent's food supply if this animal group receives adequate attention and is used integrated properly in crop and livestock systems which characterize smallholder farming sector in Africa. Because they have evolved over time to accommodate the various climatic conditions and environmental pressures on the continent, Africa's native animal genetic resources are particularly resilient. Indirectly, the impact of climate change offers a chance to use native animal genetics from Africa. The use of local animal genetic diversity has the potential to substantially improve Africa's food security landscape hence should be given special consideration for sociocultural, environmental, and economic aspects, and with regard for smallholder farmer-specific factors of interest. African animal genetic resources have contributed significantly to the food and nutrition security aspects of the millions of people in their communities of origin and custody in Africa. The purpose of the perception piece is to educate the reader about the fundamental mechanisms that control the use of continental animal genetic resources and how the outlook for these mechanisms can be manipulated in the future for the benefit of improving food security in Africa. The discussion provides in-depth insight into the pertinent literature in understanding the significance of local animal genetic resources in terms of their contribution to food security in Africa.