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

Statistical method for testing the neutral mutation hypothesis by DNA polymorphism.

So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

Genetics and analysis of quantitative traits

Gene families are growing rapidly, but standard methods for inferring phylogenies do not scale to alignments with over 10,000 sequences. We present FastTree, a method for constructing large phylogenies and for estimating their reliability. Instead of storing a distance matrix, FastTree stores sequence profiles of internal nodes in the tree. FastTree uses these profiles to implement neighbor-joining and uses heuristics to quickly identify candidate joins. FastTree then uses nearest-neighbor interchanges to reduce the length of the tree. For an alignment with N sequences, L sites, and a different characters, a distance matrix requires O(N^2) space and O(N^2 L) time, but FastTree requires just O( NLa + N sqrt(N) ) memory and O( N sqrt(N) log(N) L a ) time. To estimate the tree's reliability, FastTree uses local bootstrapping, which gives another 100-fold speedup over a distance matrix. For example, FastTree computed a tree and support values for 158,022 distinct 16S ribosomal RNAs in 17 hours and 2.4 gigabytes of memory. Just computing pairwise Jukes-Cantor distances and storing them, without inferring a tree or bootstrapping, would require 17 hours and 50 gigabytes of memory. In simulations, FastTree was slightly more accurate than neighbor joining, BIONJ, or FastME; on genuine alignments, FastTree's topologies had higher likelihoods. FastTree is available at http://microbesonline.org/fasttree.

/pdf/fast-tree-computing-large-minimum-evolution-trees-with-4grq0gwfpy.pdf

Fast Tree: Computing Large Minimum-Evolution Trees with Profiles instead of a Distance Matrix

Evolutionary neuroecology of olfactory-mediated sexual communication and host specialization in Drosophila – a review – M. A. Khallaf & M. Knaden (https://doi.org/10.1111/eea.13143). 

Editor’s Choice: April 2022

Parasitoid insects are an example of partners in an intricate host– parasite relationship. As the developing parasitoid feeds from the host, it has lost the ability to synthesize crucial nutrients, such as lipids. The genetic infrastructure for lipid accumulation seems to have remained intact though. Considering that some Hymenoptera have lost the parasitoid lifestyle and secondarily adopted phytophagy, the question arises: did these wasps regain the ability to store lipids? Lammers and colleagues investigate this question in the seedfeeding larvae of the Chalcidoidea Megastigmus aculeatus (Swederus) (Torymidae) and Bruchophagus platypterus (Walker) (Eurytomidae). They find that the larvae lose lipids (fat reserves) during development and that these species have not regained the ability to synthesize lipids. The authors conclude that the seeds contain sufficient nutrients to sustain development and enable a phytophagous lifestyle. In an evolutionary context, lack of lipid accumulation may therefore not hamper diet shifts in the parasitoid Hymenoptera.

Editor's Choice: June 2022

In 2021, Entomologia Experimentalis et Applicata has published more than 100 articles, including six mini-reviews, and one special issue. The manuscript submission rate (as well as the rejection rate) remained high. As of 2022, two long-term members of our circle of Associate Editors stepped down (Peter Follett and Marc Rhainds) and two new members have joined (Anke Steppuhn and Eric Moise). We expanded our Editorial Board with three members from China. 

Note from the Editors – March 2022

Parasitoids are in a continuous arms race with their host for survival. This battle has led to numerous evolutionary innovations, including the recruitment of additional parties, such as the host microbiome. Kryukov and colleagues demonstrate that parasitization by Habrobracon brevicornis (Hymenoptera: Braconidae) leads to differences in the microbial composition of larvae of the wax moth, Galleria mellonella (Lepidoptera: Pyralidae). They envision that the parasitoid's venom alters the lipid composition of the host larval cuticle, which increases its susceptibility to infection, thereby putting an extra challenge on the host immune system, which in turn may increase the survival chance of the parasitoid's offspring. This study is an intriguing example of the intricate interactions between parasitoids and their hosts.

Leo W. Beukeboom

Papers

Editor’s Choice: April 2022

Editor's Choice: June 2022

Note from the Editors – March 2022

Editor's Choice: October 2022

Editor's Choice: September 2023