The nucleus of mammalian cells is highly compartmentalized both in terms of DNA and protein organization. Speckles are large membrane-less irregularly shaped nuclear condensates with a dynamic composition of hundreds of different proteins, many of which are involved in RNA splicing. Evidence from recent studies points towards an interesting connection between the evolution of nuclear speckles and genome structure in terms of base composition, gene clustering and 3D-genome organization...Read more

Welcome to another HPA image of the week! This week's image was brought to us by citizen scientists in Project Discovery, and specifically by Selphentine who pointed out several nice examples of proteins localized to "nuclear speckles". In Project Discovery, citizen scientists are refining our annotations for proteins within the nucleus by labeling these nuclear speckles, previously not annotated in the atlas.

The protein stained in Fig 1. is an image of DEAD (Asp-Glu-Ala-Asp) box polypeptide 39B (DDX39B) seen in the nuclear speckles. This sample shows MCF-7 cells, a human adenocarcinoma cell line from breast cancer...Read more