K homology (KH) RNA-binding domain, type I; KH binds single-stranded RNA or DNA. It is found in a wide variety of proteins including ribosomal proteins, transcription factors and post-transcriptional modifiers of mRNA. There are two different KH domains that belong to different protein folds, but they share a single KH motif. The KH motif is folded into a beta alpha alpha beta unit. In addition to the core, type II KH domains (e.g. ribosomal protein S3) include an N-terminal extension and type I KH domains (e.g. hnRNP K) contain a C-terminal extension. Some KH-I superfamily members contain a divergent KH domain that lacks the RNA-binding GXXG motif. Some others have a mutated GXXG motif which may or may not have nucleic acid binding ability.

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gi 2774472534   1 MARSSRSDPDRPCVLPGNPSWIQDARYL 28
Cdd:cd22396    36 IAPDSGGLPERPCTLTGTPDAIETAKRL 63

first type I K homology (KH) RNA-binding domain found in the FUBP family RNA/DNA-binding proteins; The far upstream element-binding protein (FUBP) family includes FUBP1-3. FUBP1, also called FBP, or FUSE-binding protein 1, or DNA helicase V, or DH V, binds RNA and single-stranded DNA (ssDNA) and may act both as activator and repressor of transcription. It regulates MYC expression by binding to a single-stranded far-upstream element (FUSE) upstream of the MYC promoter. FUBP2, also called FUSE-binding protein 2, or KH type-splicing regulatory protein (KSRP), or p75, is a single-strand nucleic acid binding protein implicated in a variety of cellular processes, including splicing in the nucleus, mRNA decay, maturation of miRNA, and transcriptional control of proto-oncogenes such as c-myc. It regulates the stability and/or translatability of many mRNA species, encoding immune-relevant proteins, either by binding to AU-rich elements (AREs) of mRNA 3'UTR or by facilitating miRNA biogenesis to target mRNA. FUBP3, also called FUSE-binding protein 3, or MARTA2, was previously shown to mediate dendritic targeting of MAP2 mRNA in neurons. It may interact with single-stranded DNA from the far-upstream element (FUSE) and activate gene expression. It is required for beta-actin mRNA localization. It also interacts with fibroblast growth factor 9 (FGF9) 3'-UTR UG repeats and positively controls FGF9 expression through increasing translation of FGF9 mRNA. FUBP proteins contain four K-homology (KH) RNA-binding domains. The model corresponds to the first one.

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gi 2774472534   1 MARSSRSDPDRPCVLPGNPSWIQDARYL 28
Cdd:cd22396    36 IAPDSGGLPERPCTLTGTPDAIETAKRL 63

first type I K homology (KH) RNA-binding domain found in the FUBP family RNA/DNA-binding proteins; The far upstream element-binding protein (FUBP) family includes FUBP1-3. FUBP1, also called FBP, or FUSE-binding protein 1, or DNA helicase V, or DH V, binds RNA and single-stranded DNA (ssDNA) and may act both as activator and repressor of transcription. It regulates MYC expression by binding to a single-stranded far-upstream element (FUSE) upstream of the MYC promoter. FUBP2, also called FUSE-binding protein 2, or KH type-splicing regulatory protein (KSRP), or p75, is a single-strand nucleic acid binding protein implicated in a variety of cellular processes, including splicing in the nucleus, mRNA decay, maturation of miRNA, and transcriptional control of proto-oncogenes such as c-myc. It regulates the stability and/or translatability of many mRNA species, encoding immune-relevant proteins, either by binding to AU-rich elements (AREs) of mRNA 3'UTR or by facilitating miRNA biogenesis to target mRNA. FUBP3, also called FUSE-binding protein 3, or MARTA2, was previously shown to mediate dendritic targeting of MAP2 mRNA in neurons. It may interact with single-stranded DNA from the far-upstream element (FUSE) and activate gene expression. It is required for beta-actin mRNA localization. It also interacts with fibroblast growth factor 9 (FGF9) 3'-UTR UG repeats and positively controls FGF9 expression through increasing translation of FGF9 mRNA. FUBP proteins contain four K-homology (KH) RNA-binding domains. The model corresponds to the first one.

                          10        20
                  ....*....|....*....|....*...
gi 2774472534   1 MARSSRSDPDRPCVLPGNPSWIQDARYL 28
Cdd:cd22396    36 IAPDSGGLPERPCTLTGTPDAIETAKRL 63