Quick links to useful resources
Cell-PLoc 2.0 - predicting subcellular localization of proteins in different organisms (non-human)
PhosphoSitePlus - database for post-translational modifications
OpenCell - Protein localization and interaction atlas in human cells
OpenOrganelle - electron micrographs of various organelles
JASPAR - a collection of transcription factor DNA-binding preferences, modeled as matrices.