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

Since the first application of the surface plasmon resonance (SPR) phenomenon for sensing almost two decades ago, this method has made great strides both in terms of instrumentation development and applications. SPR sensor technology has been commercialized and SPR biosensors have become a central tool for characterizing and quantifying biomolecular interactions. This paper attempts to review the major developments in SPR technology. Main application areas are outlined and examples of applications of SPR sensor technology are presented. Future prospects of SPR sensor technology are discussed.

Surface plasmon resonance sensors: review

CA : A Cancer Journal for Clinicians

The ionotropic glutamate receptors are ligand-gated ion channels that mediate the vast majority of excitatory neurotransmission in the brain. The cloning of cDNAs encoding glutamate receptor subunits, which occurred mainly between 1989 and 1992 ([Hollmann and Heinemann, 1994][1]), stimulated this

/pdf/the-glutamate-receptor-ion-channels-560mntczdb.pdf

The glutamate receptor ion channels

In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system.

/pdf/biological-properties-of-extracellular-vesicles-and-their-bef7axtqvb.pdf

Biological properties of extracellular vesicles and their physiological functions

Calcium pumps of the plasma membrane (also known as plasma membrane Ca2+-ATPases or PMCAs) are responsible for the expulsion of Ca2+ from the cytosol of all eukaryotic cells. Together with Na+/Ca2+ exchangers, they are the major plasma membrane transport system responsible for the long-term regulation of the resting intracellular Ca2+concentration. Like the Ca2+ pumps of the sarco/endoplasmic reticulum (SERCAs), which pump Ca2+ from the cytosol into the endoplasmic reticulum, the PMCAs belong to the family of P-type primary ion transport ATPases characterized by the formation of an aspartyl phosphate intermediate during the reaction cycle. Mammalian PMCAs are encoded by four separate genes, and additional isoform variants are generated via alternative RNA splicing of the primary gene transcripts. The expression of different PMCA isoforms and splice variants is regulated in a developmental, tissue- and cell type-specific manner, suggesting that these pumps are functionally adapted to the physiological need...

https://www.physiology.org/doi/pdf/10.1152/physrev.2001.81.1.21

Role of alternative splicing in generating isoform diversity among plasma membrane calcium pumps.

Complete primary structure of a human plasma membrane Ca2+ pump.

Multiple divergent mRNAs code for a single human calmodulin.

Calcium entering the cell from the outside or from intracellular organelles eventually must be returned to the extracellular milieu or to intracellular storage organelles. The two major systems capable of pumping Ca 2+ against its large concentration gradient out of the cell or into the sarco/endoplasmatic reticulum are the plasma membrane Ca 2+ ATPases (PMCAs) and the sarco/endoplasmic reticulum Ca 2+ ATPases (SERCAs), respectively. In mammals, multigene families code for these Ca 2+ pumps and additional isoform subtypes are generated via alternative splicing. PMCA and SERCA isoforms show developmental-, tissue- and cell type-specific patterns of expression. Different PMCA and SERCA isoforms are characterized by different regulatory and kinetic properties that likely are optimized for the distinct functional tasks fulfilled by each pump in setting resting cytosolic or intra-organellar Ca 2+ levels, and in shaping intracellular Ca 2+ signals with spatial and temporal resolution. The loss or malfunction of specific Ca 2+ pump isoforms is associated with defects such as deafness, ataxia or heart failure. Understanding the involvement of different Ca 2+ pump isoforms in the pathogenesis of disease allows their identification as therapeutic targets for the development of selective strategies to prevent or combat the progression of these disorders.

Calcium pumps of plasma membrane and cell interior.

http://molneuro.kaist.ac.kr/contents/pdf/1998_22.pdf

Emanuel E. Strehler

Papers

Role of alternative splicing in generating isoform diversity among plasma membrane calcium pumps.

Complete primary structure of a human plasma membrane Ca2+ pump.

Multiple divergent mRNAs code for a single human calmodulin.

Calcium pumps of plasma membrane and cell interior.

Plasma Membrane Ca2+ ATPase Isoform 4b Binds to Membrane-associated Guanylate Kinase (MAGUK) Proteins via Their PDZ (PSD-95/Dlg/ZO-1) Domains