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By the end of this section, you will be able to:Discuss why every cell does not express all of its genesDescribe how prokaryotic gene regulation occurs at the transcriptional levelDiscuss how eukaryotic gene regulation occurs at the epigenetic, transcriptional, post-transcriptional, translational, and post-translational levels

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Hematopoietic stem cells (HSCs) are immature cells that can develop into all types of blood cells, making them critical regulators of blood composition. However, during aging, HSCs undergo a process called senescence, in which their functionality starts to fade, leading to issues like reduced immune cell populations or leukemia. HSC senescence is influenced by various age-related factors, like accumulated DNA damage or epigenetic (non-DNA-altering) changes in gene expression, and it’s regulated by small RNA molecules known as microRNAs (miRNAs). For example, the miR-212/132 cluster binds to the FOXO3 gene to affect HSC life cycles, function, and survival and is upregulated with aging, while miR-125b, which can help HSCs resist stress and cell death, is downregulated in aging HSCs..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"The concept of trained immunity suggests that exposure to nonpathogenic microbes or their metabolites can enhance an organism’s immune response later in life. But while trained immunity has been addressed by many studies focusing on vertebrate animals, little is known about its role in invertebrates. A recent study showed that microorganism exposure early in development increased the survival of the Pacific oyster when challenged with infectious disease. Researchers cultured Pacific oysters in filtered and UV-treated seawater that had either been enriched with naturally occurring microbes or unmanipulated as a control. These oysters and their offspring were then exposed to the virus that causes Pacific oyster mortality syndrome, a disease that devastates oyster farms worldwide. The team found increased survival not only among the oysters directly exposed to the microbe-enriched seawater but also among their progeny..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"N6-methyl-adenosine (m⁶A) methylation is the most abundant epigenetic modification on mRNA and lncRNA. This modification is regulated by m⁶A writers, readers, and erasers, and its proper regulation is critical for innate and adaptive immunity, especially since m⁶A can play different roles depending on the transcript region, cell type, or specific regulators involved. For example, in the innate immune system, m⁶A can promote the antitumor and antiviral activity of NK cells. It can also activate disease- fighting M1 macrophages, reduce inflammation, and encourage dendritic cell maturation and activity. On the other hand, m⁶A can prevent dendritic cells from cross-presenting tumor antigens to prime T cells, hindering the antitumor response. In the adaptive immune system, m⁶A promotes T cell homeostasis but also suppresses T follicular helper cell development and it can either exacerbate or inhibit HIV-1 infection in CD4⁺ T cells..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"In prokaryotes, DNA methylation participates in numerous cellular processes. Most studies on prokaryotic methylation have been conducted in culturable microbes, but the majority of environmental bacteria aren’t culturable. Therefore, the real-world diversity and functions of microbial methylation remain unclear. To learn more, researchers recently analyzed the microbes in Pacific Ocean seawater samples using meta-epigenomics. Through short- and long-read sequencing, they reconstructed 15,056 viral, 252 prokaryotic, 56 giant viral, and 6 eukaryotic metagenome-assembled genomes, most of which represented novel taxa. Single-molecule real-time (SMRT) sequencing revealed that DNA methylation was present across the dominant bacterial, archaeal, and viral populations and showed that epigenetic marks were correlated with population differentiation..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Atherosclerosis and vascular injury are leading causes of cardiovascular disease worldwide Low-density lipoprotein (LDL) plays a key role in these diseases by inducing inflammation and oxidative stress Endothelial cells can repair blood vessels damaged by LDL But how endothelial cells mature and take on this task is unclear In a recent study, researchers examined the maturation and antioxidative activity of endothelial cells Molecular biology techniques revealed that the differentiation of endothelial cells was regulated by a microRNA molecule called miR-544 miR-544 inhibited the expression of genes involved in maintaining stem cell pluripotency Promoting endothelial cell maturation and vascular formation Transplanting endothelial cells expressing miR-544 also improved the outcome of oxidative stress injury in mice Although these studies must be further evaluated in humans The results suggest that targeting miR-544 may help with regeneration and repair of blood vessels after vascular injury Impr.."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.