Good question! Auxenochlorella have been sampled from seawater (especially A. symbiontica), but to my knowledge they are only known as symbionts of freshwater hydra and sponges. But they could be useful to investigate the molecular basis of these symbioses

(6/6) Overall, we found that the “yeast-like” processes of allodiploid hybridisation, mitotic recombination, loss-of-heterozygosity and aneuploidy all occur in an alga, showing the generality of these forces to vegetatively diploid eukaryotes

(5/6) We also saw aneuploidies in two strains and we successfully transformed a trisomic chromosome using an allele-specific construct. We’re hopeful that we can utilise these redundant chromosomes for synthetic biology by sequential introduction of transgenes

(4/6) Most remarkably, our reference strain UTEX 250 is an allodiploid hybrid of two close relatives, A. protothecoides and A. symbiontica, that are distinguished by highly rearranged karyotypes. The UTEX 250 sub-genomes have been further shuffled by rearrangements and recombination

(3/6) Unlike most green algae, Auxenochlorella are vegetatively diploid and their genomes are shaped by evolutionary phenomena that reflect this. While these processes are well-understood in yeast, we were surprised to see extensive mitotic recombination and loss-of-heterozygosity in several strains

(2/6) We introduce selectable markers, inducible promoters and fluorescent reporters for protein localisation, and @marcoaduenas.bsky.social has written a protocol for HR-based transformation: dx.doi.org/10.17504/protocols.io.x54v922mql3e/v1. All credit to a team led by Jeff Moseley here

(1/6) First and foremost, Auxenochlorella spp. are oily green algae that can be readily transformed by homologous recombination, enabling efficient site-specific transformation of the nuclear genome. This is a first for chlorophytes, and we hope that it will facilitate lots of interesting research