抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

https://www.cell.com/cell/pdf/S0092-8674(05)00109-1.pdf

Mitochondria, Oxidants, and Aging

The nematode Caenorhabditis elegans ages and dies in a few weeks, but humans can live for 100 years or more. Assuming that the ancestor we share with nematodes aged rapidly, this means that over evolutionary time mutations have increased lifespan more than 2,000-fold. Which genes can extend lifespan? Can we augment their activities and live even longer? After centuries of wistful poetry and wild imagination, we are now getting answers, often unexpected ones, to these fundamental questions.

The genetics of ageing

The mechanistic target of rapamycin (mTOR) coordinates eukaryotic cell growth and metabolism with environmental inputs, including nutrients and growth factors. Extensive research over the past two decades has established a central role for mTOR in regulating many fundamental cell processes, from protein synthesis to autophagy, and deregulated mTOR signaling is implicated in the progression of cancer and diabetes, as well as the aging process. Here, we review recent advances in our understanding of mTOR function, regulation, and importance in mammalian physiology. We also highlight how the mTOR signaling network contributes to human disease and discuss the current and future prospects for therapeutically targeting mTOR in the clinic.

mTOR Signaling in Growth, Metabolism, and Disease

Proper regulation and management of energy, substrate diversity and quantity, as well as macromolecular synthesis and breakdown processes, are fundamental to cellular and organismal survival and are paramount to health. Cellular and multicellular organization are defended by the immune response, a robust and critical system through which self is distinguished from non-self, pathogenic signals are recognized and eliminated, and tissue homeostasis is safeguarded. Many layers of evolutionarily conserved interactions occur between immune response and metabolism. Proper maintenance of this delicate balance is crucial for health and has important implications for many pathological states such as obesity, diabetes, and other chronic non-communicable diseases.

Inflammation, metaflammation and immunometabolic disorders

JNK Extends Life Span and Limits Growth by Antagonizing Cellular and Organism-Wide Responses to Insulin Signaling

JNK Signaling Confers Tolerance to Oxidative Stress and Extends Lifespan in Drosophila

Fat metabolism, reproduction, and aging are intertwined regulatory axes; however, the mechanism by which they are coupled remains poorly understood. We found that germline stem cells (GSCs) actively modulate lipid hydrolysis in Caenorhabditis elegans, which in turn regulates longevity. GSC arrest promotes systemic lipolysis via induction of a specific fat lipase. Subsequently, fat mobilization is promoted and life span is prolonged. Constitutive expression of this lipase in fat storage tissue generates lean and long-lived animals. This lipase is a key factor in the lipid hydrolysis and increased longevity that are induced by decreased insulin signaling. These results suggest a link between C. elegans fat metabolism and longevity.

/pdf/fat-metabolism-links-germline-stem-cells-and-longevity-in-c-4thhy5z93l.pdf

Fat metabolism links germline stem cells and longevity in C. elegans.

Sensitive and specific visualization of small biomolecules in living systems is highly challenging. We report stimulated Raman-scattering imaging of alkyne tags as a general strategy for studying a broad spectrum of small biomolecules in live cells and animals. We demonstrate this technique by tracking alkyne-bearing drugs in mouse tissues and visualizing de novo synthesis of DNA, RNA, proteins, phospholipids and triglycerides through metabolic incorporation of alkyne-tagged small precursors.

http://www.columbia.edu/cu/chemistry/groups/min/pdf/20-Alkyne_SRS.pdf

Meng C. Wang

Papers

JNK Extends Life Span and Limits Growth by Antagonizing Cellular and Organism-Wide Responses to Insulin Signaling

JNK Signaling Confers Tolerance to Oxidative Stress and Extends Lifespan in Drosophila

Fat metabolism links germline stem cells and longevity in C. elegans.

Live-cell imaging of alkyne-tagged small biomolecules by stimulated Raman scattering

Microbial Genetic Composition Tunes Host Longevity.