hattrill
commented
2 years ago For PMID:34478447 atlas is described as: "everal lines of evidence suggest that Atlas is a transition protein that facilitates the change from histone-based to protamine-based chromatin packaging in spermatid nuclei. Atlas localizes throughout spermatid nuclei (Fig 6) and has biochemical properties consistent with direct DNA interaction. The protein appears specifically at the late canoe stage of nuclear compaction (Fig 5). Its lack of overlap with testis-specific histones (Fig 5B), partial overlap with Mst35Bb (Fig 5D), removal from needle-stage nuclei (Fig 6) and absence from mature sperm (Figs 5 and 6) are all consistent with the expression profile of a transition protein. Several other transition proteins have been characterized in D. melanogaster, including Tpl94D, thmg-1, thmg-2, and Mst84B [53,58,59]. Collectively, the transition proteins vary in the stage of nuclear condensation at which they first appear and the range of nuclear shapes over which they are found [79], but otherwise match Atlas in their biochemical properties, transient expression, and localization throughout the nucleus. Compared to these other transition proteins, Atlas is present over a fairly narrow range of nuclear condensation stages and reaches its peak expression just prior to the onset of individualization. Atlas is also the only transition protein gene characterized to date whose removal disrupts fertility, as Tpl94D, thmg-1, thmg-2 and Mst84B mutants are all fertile [53,58,59]. This may reflect the relatively later timing of Atlas’s expression in spermatid nuclei, reduced functional redundancy between DNA-binding proteins at the later stages of condensa- tion, a potential interaction between Atlas and an essential protamine-like protein, and/or a more stringent requirement for DNA binding at these stages"
Need to understand more about mechanism to give an MF. Can move BP from " spermatogenesis, exchange of chromosomal proteins" to "sperm DNA condensation".
Address these issues on histone exchange as this process will be replaced by a function and the BPs need to be re-annotated. http://amigo.geneontology.org/amigo/term/GO:0035093#display-lineage-tab https://docs.google.com/spreadsheets/d/13Sys5a4tYDCtXJKzwZ29K-0VCCN_IMl9SGMchl_QLGM/edit#gid=0