 Other methods for <unk> the cellular location of proteins requires the use of known <unk> markers for regions such as the ER , the <unk> , <unk> or <unk> , mitochondria , <unk> , plasma membrane , etc . With the use of <unk> <unk> versions of these markers or of antibodies to known markers , it becomes much simpler to identify the localization of a protein of interest . For example , indirect <unk> will allow for fluorescence <unk> and demonstration of location . <unk> <unk> are used to label cellular compartments for a similar purpose . 
