Do trees get old? This is not a trivial question: indeterminate growth distinguishes plants from many (if not most) animals, and so while they obviously get older, they do not necessarily age, or senesce. But it turns out that accumulation of mutations in very old Aspens affects pollen quality1, which means that clonal trees do suffer from old age and may eventually become extinct.
Although (it says here) removal of pubic hair has been described as a “new norm”, little is known about the pubic hair removal patterns of sexually active women in the United States. Now the research has been done2, and there are some interesting findings: although total removal of pubic hair is relatively uncommon, those women who are in a sexual relationship (but not married), who have examined their genitals in the last month, or who have received oral sex in the last month are more likely to have removed all their pubic hair. These women also report a more positive genital self-image and score higher on a sexual function scale, although tellingly not on an orgasm subscale.
For this week’s dose of pretty cell biology I’m going to point you to a paper on the dynamics of metastasis. Just as leucocytes famously roll along the vasculature and then stick and extravasate through the endothelial wall, so do metatstatic cells. The difference being that we don’t know a lot about how the latter do it. Unsurprisingly, the process depends on ß1-integrins3; the clever part is that the investigators looked at the behaviour of human adenocarcinoma cells in everyone’s favourite transparent model, zebrafish. The paper, unfortunately, isn’t free to view, but there are some pretty movies in the supplemental information, which is.
You’re probably familiar with our ‘Top 7’ series at The Scientist. Every week we bring you the best of a particular Faculty, and every month we publish the best overall papers according to our Faculty. But because we allow (indeed, we encourage) multiple evaluations of a single paper, these lists are not static, and it’s worth remembering they represent a snapshot in time. Yesterday, for example, we featured seven papers in Immunology, and this morning one of those papers, Activation of beta-catenin in dendritic cells regulates immunity versus tolerance in the intestine4, attracted another evaluation, bumping it up the list. The paper shows how Wnt-ß-catenin signaling in intestinal dendritic cells keeps the immune system from responding inappropriately to commensal gut bacteria. Another remarkable thing about this paper is that Faculty Members from as far apart as Osaka, London, Brazil and Tennessee have evaluated it, nicely demonstrating the breadth and variety of the Faculty.