Group:MUZIC:Enigma Family: Difference between revisions

Three member proteins have extensively been described and characterized within this subfamily: '''Enigma''' protein, '''Enigma Homologue''' (ENH) protein and '''ZASP/Cypher/Oracle''' (ZASP<ref>PMID:10427098</ref> being the human orthologue of cypher<ref>PMID:10391924</ref> in mouse, also identified by independent researchers as oracle<ref>PMID:10727866</ref>). The family name - ''Enigma'' - possibly was inspired by the intricately complicated splice variants identified in the first member, a common feature in all member proteins, as well as their redundant, indinstinct functions in the cytoskeleton. Didactically, protein members of the enigma subfamily typically possess within their structure: '''(1)''' an N-terminal PDZ domain (domain named after first three proteins where it was initially characterized i.e. '''P'''SD 95, '''D'''isc large protein and '''Z'''onula Occludens 1), and '''(2)''' three C-terminal LIM domains (domain named after three proteins where it was first characterized '''L'''in-11, '''I'''sl1 and '''M'''ec-3)<ref>PMID:20042479</ref>. The Enigma member proteins have all been located to the mammalian muscle cells, some specific to the heart and skeletal muscle Z-disk. They interact via their PDZ domains with protein components of the Z-disk and also recruit signalling molecules via their LIM domains or internal motifs, for example ''ZM motif'' (ZASP-like motif which is sandwiched between the PDZ- and LIM-domains in ZASP)<ref>doi:10.1161/CIRCRESAHA.110.225615</ref>. These interactions via their PDZ- and LIM-domains suggest roles important for targeting/sustaining interacting protein complexes within the myofibrillar sarcomere for a physiologically functional muscle.

[[Image:Enigma_family.png|right|thumb|600px|Topological map of the PDZ- and LIM-domains in the first isoforms of human Enigma subfamily members [http://www.uniprot.org/uniprot/O75112#section_features)][http://www.uniprot.org/uniprot/Q96HC4#section_alternative][http://www.uniprot.org/uniprot/Q9NR12#section_features]]]

'''Enigma''' protein

alternatively referred to as PDLIM7 (PDZ and LIM domain protein 7) is the first and representative member of the Enigma subfamily. Initially characterized in human as ~49.85 kDa, 457 amino-acid protein with an N-terminal PDZ domain and three C-terminal LIM domains <ref>PMID:7929196</ref> <ref>PMID:10359609</ref>. Five alternatively spliced isoforms are presently identified (UniProtKB ID: Q9NR12)[http://www.uniprot.org/uniprot/Q9NR12#section_features].

==Structure==