FYVE domain like superfamily; FYVE domain is a 60-80 residue double zinc finger motif-containing module named after the four proteins, Fab1, YOTB, Vac1, and EEA1. The canonical FYVE domains are distinguished from other zinc fingers by three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif, which form a compact phosphatidylinositol 3-phosphate (PtdIns3P, also termed PI3P)-binding site. They are found in many membrane trafficking regulators, including EEA1, Hrs, Vac1p, Vps27p, and FENS-1, which locate to early endosomes, specifically bind PtdIns3P, and play important roles in vesicular traffic and in signal transduction. Some proteins, such as rabphilin-3A and alpha-Rab3-interacting molecules (RIMs), are also involved in membrane trafficking and bind to members of the Rab subfamily of GTP hydrolases. However, they contain FYVE-related domains that are structurally similar to the canonical FYVE domains but lack the three signature sequences. At this point, they may not bind to phosphoinositides. In addition, this superfamily also contains the third group of proteins, caspase-associated ring proteins CARP1 and CARP2. They do not localize to membranes in the cell and are involved in the negative regulation of apoptosis, specifically targeting two initiator caspases, caspase 8 and caspase 10, which are distinguished from other FYVE-type proteins. Moreover, these proteins have an altered sequence in the basic ligand binding patch and lack the WxxD motif that is conserved only in phosphoinositide binding FYVE domains. Thus they constitute a family of unique FYVE-type domains called FYVE-like domains. The FYVE domain is structurally similar to the RING domain and the PHD finger. This superfamily also includes ADDz zinc finger domain, which is a PHD-like zinc finger motif that contains two parts, a C2-C2 and a PHD-like zinc finger.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 60391835   1 VICTACGQQVNQFqKDSIYRHPTLNVLICK----------------------RWCAEGGNLICCDSCHNAFCKKCIWRNL 58
Cdd:cd11726   3 VRCTACGEQLNHF-SKEVHRHPVLKVLICKsclkfynsgefskdedgsdeycRWCGQGGDLICCDFCPNVFCKKCIKRNL 81

                        90       100
                ....*....|....*....|..
gi 60391835  59 GRKEISKiMNEKNEWHCYICCP 80
Cdd:cd11726  82 GRAELSR-IEESDKWKCFVCDP 102

ADDz domain found in ATRX (alpha-thalassemia/mental retardation, X-linked); ADDz_ATRX is a PHD-like zinc finger domain of ATRX, which belongs to the SNF2 family of chromatin remodeling proteins. ATRX is a large chromatin-associated nuclear protein with two domains, ADDz_ATRX at the N-terminus, followed by a C-terminal ATPase/helicase domain. The ADDz_ATRX domain recognizes a specific methylated histone, and this interaction is required for heterochromatin localization of the ATRX protein. Missense mutations in either of the two ATRX domains lead to the X-linked alpha-thalassemia and mental retardation syndrome; however the mutations in the ADDz_ATRX domain produce a more severe disease phenotype that may also relate to disturbing unknown functions or interaction sites of this domain. The ADDz domain is also present in chromatin-associated proteins cytosine-5-methyltransferase 3 (Dnmt3); it is a PHD-like zinc finger motif that contains two parts, a C2-C2 and a PHD-like zinc finger. PHD zinc finger domains have been identified in more than 40 proteins that are mainly involved in chromatin mediated transcriptional control; the classical PHD zinc finger has a C4-H-C3 motif that spans about 50-80 amino acids. In ADDz, the conserved histidine residue of the PHD finger is replaced by a cysteine, and an additional zinc finger C2-C2 like motif is located about twenty residues upstream of the C4-C-C3 motif.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 60391835   1 VICTACGQQVNQFqKDSIYRHPTLNVLICK----------------------RWCAEGGNLICCDSCHNAFCKKCIWRNL 58
Cdd:cd11726   3 VRCTACGEQLNHF-SKEVHRHPVLKVLICKsclkfynsgefskdedgsdeycRWCGQGGDLICCDFCPNVFCKKCIKRNL 81

                        90       100
                ....*....|....*....|..
gi 60391835  59 GRKEISKiMNEKNEWHCYICCP 80
Cdd:cd11726  82 GRAELSR-IEESDKWKCFVCDP 102

ADDz domain found in ATRX (alpha-thalassemia/mental retardation, X-linked); ADDz_ATRX is a PHD-like zinc finger domain of ATRX, which belongs to the SNF2 family of chromatin remodeling proteins. ATRX is a large chromatin-associated nuclear protein with two domains, ADDz_ATRX at the N-terminus, followed by a C-terminal ATPase/helicase domain. The ADDz_ATRX domain recognizes a specific methylated histone, and this interaction is required for heterochromatin localization of the ATRX protein. Missense mutations in either of the two ATRX domains lead to the X-linked alpha-thalassemia and mental retardation syndrome; however the mutations in the ADDz_ATRX domain produce a more severe disease phenotype that may also relate to disturbing unknown functions or interaction sites of this domain. The ADDz domain is also present in chromatin-associated proteins cytosine-5-methyltransferase 3 (Dnmt3); it is a PHD-like zinc finger motif that contains two parts, a C2-C2 and a PHD-like zinc finger. PHD zinc finger domains have been identified in more than 40 proteins that are mainly involved in chromatin mediated transcriptional control; the classical PHD zinc finger has a C4-H-C3 motif that spans about 50-80 amino acids. In ADDz, the conserved histidine residue of the PHD finger is replaced by a cysteine, and an additional zinc finger C2-C2 like motif is located about twenty residues upstream of the C4-C-C3 motif.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 60391835   1 VICTACGQQVNQFqKDSIYRHPTLNVLICK----------------------RWCAEGGNLICCDSCHNAFCKKCIWRNL 58
Cdd:cd11726   3 VRCTACGEQLNHF-SKEVHRHPVLKVLICKsclkfynsgefskdedgsdeycRWCGQGGDLICCDFCPNVFCKKCIKRNL 81

                        90       100
                ....*....|....*....|..
gi 60391835  59 GRKEISKiMNEKNEWHCYICCP 80
Cdd:cd11726  82 GRAELSR-IEESDKWKCFVCDP 102

Cysteine Rich ADD domain; This is a cysteine-rich domain termed ADD (ATRX-DNMT3-DNMT3L, AD-DATRX) found in ATRX proteins. Chromatin-associated human protein ATRX was originally identified because mutations in the ATRX gene cause a severe form of syndromal X-linked mental retardation called ATR-X syndrome. Mutations or knockdown of ATRX expression cause diverse effects, including altered patterns of DNA methylation, a telomere-dysfunction phenotype, aberrant chromosome segregation, premature sister chromatid separation and changes in gene expression. ATRX localizes predominantly to large, tandemly repeated regions (such as telomeres, centromeres and ribosomal DNA) associated with heterochromatin, and studies show that it directs H3.3 deposition to pericentric and telomeric heterochromatin. The ADD domain of ATRX, in which most syndrome-causing mutations occur, engages the N-terminal tail of histone H3 through two rigidly oriented binding pockets, one for unmodified Lys4 and the other for di- or trimethylated Lys9. Mutations in the ATRX ADD domain cause mislocalization of ATRX protein to heterochromatin, and this may contribute to understanding the underlying etiology of ATRX syndrome. Structure analysis of the ADD domain of ATRX revealed that it contains a PHD zinc-finger domain packed against a GATA-like zinc finger. Same structure is also found in the DNMT3 DNA methyltransferases and DNMT3L.

                         10        20        30
                 ....*....|....*....|....*....|
gi 60391835    1 VICTACGQQVNQFQKDSIYRHPTLNVLICK 30
Cdd:pfam17981 12 VNCTACGQQVNHFQRDSIYQHPVLKVLICK 41