Science literature summaries

Shfr - Location of Shfr , a new gene that rescues hybrid female viability in crosses between Drosophila simulans females and D. melanogaster males

Typically in centromeres and telomerase. Highly repetitive sequence. Have much fewer genes than euchromatin. Can silence gene expression of euchromatin. Heterochromatin increase with age and are more in males. source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7274899/

Serratia marcescens and Pseudomonas aeruginosa infection was more in axenic flies. Infections were reduced when treated with Lactobacillus Plantarum. quotidian replenishment - need to replenish microbial daily If Lactobacillus is important, then why is it not maintained: Dmel gets rids its gut of most microbes to minimize the risk of acquiring and maintaining potential pathogens. The microbiome may compete with its Drosophila host for nutrients in the gut. Our evidence indicates that Drosophila seeds its food with commensal organisms by depositing fecal matter on its food source on which the bacteria grow. Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3892787/#h2title

 Dmel microbiome is dominated by  Acetic acid bacteria (AABs), mainly genus Acetobacter (Alphaproteobacteria),  Lactic acid bacteria (LABs), mainly the genus Lactobacillus (Firmicutes) (20). And also a strong representation of other taxa, including Gammaproteobacteria (e.g., Stenotrophomonas spp.) and lactobacilli (e.g., Enterococcus spp.) (22, 23). Acetobacter fabarum, Acetobacter pomorum, Acetobacter tropicalis, Lactobacillus brevis, and Lactobacillus plantarum.

 Mutations in Lhr K18 and Hmr U79 genes enable the survival of hybrids that are otherwise lethal in wild types.