Examples of granulin protein modular structure and gene exon structure.

1. Protein Module Structure: Signal peptide not included; Hyphens indicate short intermodule sequence; g indicates a module with a typical 12 cysteine motif; g* indicates the alternative 10 cysteine motif often present in tetrapod progranulins; ğ represents the variant form of granulin module found in plants and the similar module in lamprey S4; g" represents a module missing the usual first double Cys; p indicates an N-half module (paragranulin form); q indicates a C-half module. Protein sequence recognized as a non-granulin component of the protein other than a simple intermodule sequernce is denoted by x, and in plants, the x represents a cysteine protease module.
2. Exon Structure: Hyphens indicate introns. Encoding of the N-terminal half or C-terminal half of a granulin module is indicated by n or c respectively, or by n* or c* in the case of the common alternative 5 cysteine half module forms, n" for a 4 cysteine form in lamprey, and by ň in the case of the plant N-half module or similar half module in lamprey. For Branchiostoma, c' and n' indicate that a single Cys belonging to the neighbouring module is also encoded in this exon, and |nc| indicates that the first and last single Cys in the motif are not encoded in this exon. The notation [nc rpt exons] indicates that the exon continues into highly repetitive granulin sequence, and it is uncertain precisely how many exons encode how many granulin modules. The end of the repeat contributes a C-half. For the single module Caenorhabditis elegans gene, the exon structure is unusual in that splicing occurs within the N-half sequence. The parentheses around s and n indicate parts of the signal or n sequence, and t represents a short terminal coding sequence. Exons encoding short amino acid sequences are represented by y, while x indicate exons encoding parts of non-granulin module.
Examples of granulin protein modular structure and gene exon structure.