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

http://aiocm.org/member/Immunity,%20Inflammation,%20and%20Cancer.pdf

Immunity, Inflammation, and Cancer

This issue of Pharmacological Reviews includes a new venture in the collaboration between the International Union of Pharmacology (IUPHAR) and the American Society for Pharmacology and Experimental Therapeutics (ASPET), in that a new classification of voltage-gated ion channels is outlined in this

https://pharmrev.aspetjournals.org/content/pharmrev/55/4/573.full.pdf

International Union of Pharmacology: Approaches to the Nomenclature of Voltage-Gated Ion Channels

The universality of calcium as an intracellular messenger depends on its enormous versatility. Cells have a calcium signalling toolkit with many components that can be mixed and matched to create a wide range of spatial and temporal signals. This versatility is exploited to control processes as diverse as fertilization, proliferation, development, learning and memory, contraction and secretion, and must be accomplished within the context of calcium being highly toxic. Exceeding its normal spatial and temporal boundaries can result in cell death through both necrosis and apoptosis.

The versatility and universality of calcium signalling

Ca2+ is a highly versatile intracellular signal that operates over a wide temporal range to regulate many different cellular processes. An extensive Ca2+-signalling toolkit is used to assemble signalling systems with very different spatial and temporal dynamics. Rapid highly localized Ca2+ spikes regulate fast responses, whereas slower responses are controlled by repetitive global Ca2+ transients or intracellular Ca2+ waves. Ca2+ has a direct role in controlling the expression patterns of its signalling systems that are constantly being remodelled in both health and disease.

/pdf/calcium-signalling-dynamics-homeostasis-and-remodelling-2oni038yeg.pdf

Calcium signalling: dynamics, homeostasis and remodelling

Receptor-effector coupling by G proteins

As new Ca 2ϩ channel genes are cloned, it is apparent that these two alphabetical nomenclatures will overlap at ␣ 1L , which may not mediate an L-type Ca 2ϩ current and Voltage-gated Ca 2ϩ channels mediate calcium influx in therefore may create confusion. Moreover, the present response to membrane depolarization and regulate in-alphabetical nomenclature does not reveal the structural tracellular processes such as contraction, secretion, relationships among the ␣ 1 subunits, which can be neurotransmission, and gene expression. They are mem-grouped into three families: (1) ␣ 1S , ␣ 1C , ␣ 1D , and ␣ 1F ; (2) bers of a gene superfamily of transmembrane ion chan-The complete nel proteins that includes voltage-gated K ϩ and Na ϩ amino acid sequences of these ␣ 1 subunits are more channels. The Ca 2ϩ channels that have been character-than 70% identical within a family but less than 40% ized biochemically are complex proteins composed of identical among families. These family relationships are four or five distinct subunits, which are encoded by illustrated for the more conserved transmembrane and multiple genes. The ␣ 1 subunit of 190–250 kDa is the pore domains in Figure 1. Division of calcium channels largest subunit, and it incorporates the conduction pore, into these three families is phylogenetically ancient, as the voltage sensor and gating apparatus, and the known representatives of each are found in the C. elegans ge-sites of channel regulation by second messengers, nome. Ideally, a nomenclature for Ca 2ϩ channel ␣ 1 sub-drugs, and toxins. An intracellular ␤ subunit and a trans-units should provide a systematic organization based on membrane, disulfide-linked ␣ 2 ␦ subunit complex are their structural relationships and should be coordinated components of most types of Ca 2ϩ channels. A ␥ subunit with nomenclatures for the other families of voltage-has also been found in skeletal muscle Ca 2ϩ channels, gated ion channels of different ionic selectivities (ie., K ϩ and related subunits are expressed in heart and brain. and Na ϩ). Although these auxiliary subunits modulate the proper-For these reasons, we wish to propose a new nomen-ties of the channel complex, the pharmacological and clature of voltage-gated Ca 2ϩ channels (Table 1), which electrophysiological diversity of Ca 2ϩ channels arises is more systematic and mimics the well-defined K ϩ primarily from the existence of multiple forms of ␣ 1 sub-channel nomenclature (Chandy et al., 1991). This no-units. Mammalian ␣ 1 …

Lutz Birnbaumer

Papers

Receptor-effector coupling by G proteins

Letter to the EditorNomenclature of Voltage-Gated Calcium Channels

The TRP channels, a remarkably functional family.

The Glucagon-sensitive Adenyl Cyclase System in Plasma Membranes of Rat Liver V. AN OBLIGATORY ROLE OF GUANYL NUCLEOTIDES IN GLUCAGON ACTION

trp, a Novel Mammalian Gene Family Essential for Agonist-Activated Capacitative Ca2+ Entry