Circadian regulator that acts as a transcription factor and generates a rhythmic output with a period of about 24 hours. Oscillates in antiphase to the cycling observed for period (PER) and timeless (TIM). According to PubMed:9742131, reaches peak abundance within several hours of the dark-light transition at ZT0 (zeitgeber 0), whereas PubMed:9616122 describes bimodal oscillating expression with maximum at ZT5 and ZT23. Clock-cycle heterodimers activate cycling transcription of PER and TIM by binding to the E-box (3'-CACGTG-5') present in their promoters. Once induced, Period and Timeless block Clock's ability to transactivate their promoters. Drosophila melanogaster (taxid: 7227)
BMAL1/2-CLOCK heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. Activates transcription of PER1 and PER2. This transcription is inhibited in a feedback loop by PER and CRY proteins. May play a role in DNA damage response (DDR) signaling during the S phase.
Gallus gallus (taxid: 9031)
>sp|Q6YGZ4|CLOCK_TYTAL Circadian locomoter output cycles protein kaput OS=Tyto alba GN=CLOCK PE=2 SV=1
BMAL1/2-CLOCK heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. Activates transcription of PER1 and PER2. This transcription is inhibited in a feedback loop by PER and CRY proteins. May play a role in DNA damage response (DDR) signaling during the S phase.
Tyto alba (taxid: 56313)
>sp|Q99743|NPAS2_HUMAN Neuronal PAS domain-containing protein 2 OS=Homo sapiens GN=NPAS2 PE=2 SV=3
Score = 82.0 bits (201), Expect = 9e-16, Method: Composition-based stats.
Identities = 37/59 (62%), Positives = 46/59 (77%)
Query: 20 DTDDKDDSKRKSRNLSEKKRRDQFNMLINELCTMVSTNNRKMDKSTVLKSTIAFLKNYN 78
D D+KD +KR SRN SEKKRRDQFN+LI EL +M+ N RKMDK+TVL+ I FL+ +N
Sbjct: 2 DEDEKDRAKRASRNKSEKKRRDQFNVLIKELSSMLPGNTRKMDKTTVLEKVIGFLQKHN 60
BMAL1-NPAS2 heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. This transcription is inhibited in a feedback loop by PER, and also by CRY proteins.
Homo sapiens (taxid: 9606)
>sp|P97460|NPAS2_MOUSE Neuronal PAS domain-containing protein 2 OS=Mus musculus GN=Npas2 PE=1 SV=1
Score = 81.6 bits (200), Expect = 1e-15, Method: Composition-based stats.
Identities = 37/59 (62%), Positives = 46/59 (77%)
Query: 20 DTDDKDDSKRKSRNLSEKKRRDQFNMLINELCTMVSTNNRKMDKSTVLKSTIAFLKNYN 78
D D+KD +KR SRN SEKKRRDQFN+LI EL +M+ N RKMDK+TVL+ I FL+ +N
Sbjct: 2 DEDEKDRAKRASRNKSEKKRRDQFNVLIKELSSMLPGNTRKMDKTTVLEKVIGFLQKHN 60
BMAL1-NPAS2 heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. This transcription is inhibited in a feedback loop by PER, and also by CRY proteins.
Mus musculus (taxid: 10090)
>sp|Q5ZQU2|NPAS2_CHICK Neuronal PAS domain-containing protein 2 OS=Gallus gallus GN=NPAS2 PE=2 SV=1
Score = 81.3 bits (199), Expect = 2e-15, Method: Composition-based stats.
Identities = 37/59 (62%), Positives = 46/59 (77%)
Query: 20 DTDDKDDSKRKSRNLSEKKRRDQFNMLINELCTMVSTNNRKMDKSTVLKSTIAFLKNYN 78
D D+KD +KR SRN SEKKRRDQFN+LI EL +M+ N RKMDK+TVL+ I FL+ +N
Sbjct: 2 DEDEKDRAKRASRNKSEKKRRDQFNVLIKELSSMLPGNTRKMDKTTVLEKVIGFLQKHN 60
BMAL1-NPAS2 heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. This transcription is inhibited in a feedback loop by PER, and also by CRY proteins.
ARNTL/2-CLOCK heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. Activates transcription of PER1 and PER2. This transcription is inhibited in a feedback loop by PER and CRY proteins. Has intrinsic histone acetyltransferase activity and this enzymatic function contributes to chromatin-remodeling events implicated in circadian control of gene expression. Acetylates primarily histones H3 and H4. Acetylates also a non-histone substrate: ARNTL. Plays a role in DNA damage response (DDR) signaling during the S phase.
ARNTL/2-CLOCK heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. Activates transcription of PER1 and PER2. This transcription is inhibited in a feedback loop by PER and CRY proteins. Has intrinsic histone acetyltransferase activity and this enzymatic function contributes to chromatin-remodeling events implicated in circadian control of gene expression. Acetylates primarily histones H3 and H4. Acetylates also a non-histone substrate: ARNTL. Plays a role in DNA damage response (DDR) signaling during the S phase.
ARNTL/2-CLOCK heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. Activates transcription of PER1 and PER2. This transcription is inhibited in a feedback loop by PER and CRY proteins. Has intrinsic histone acetyltransferase activity and this enzymatic function contributes to chromatin-remodeling events implicated in circadian control of gene expression. Acetylates primarily histones H3 and H4. Acetylates also a non-histone substrate: its own partner, ARNTL. Plays a role in DNA damage response (DDR) signaling during the S phase.
ARNTL/2-CLOCK heterodimers activate E-box element (3'-CACGTG-5') transcription of a number of proteins of the circadian clock. Activates transcription of PER1 and PER2. This transcription is inhibited in a feedback loop by PER and CRY proteins. Has intrinsic histone acetyltransferase activity and this enzymatic function contributes to chromatin-remodeling events implicated in circadian control of gene expression. Acetylates primarily histones H3 and H4. Acetylates also a non-histone substrate: ARNTL. Plays a role in DNA damage response (DDR) signaling during the S phase.
Nannospalax galili (taxid: 1026970)
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Close Homologs in the Non-Redundant Database Detected by BLAST
>gnl|CDD|238036 cd00083, HLH, Helix-loop-helix domain, found in specific DNA- binding proteins that act as transcription factors; 60-100 amino acids long
A DNA-binding basic region is followed by two alpha-helices separated by a variable loop region; HLH forms homo- and heterodimers, dimerization creates a parallel, left-handed, four helix bundle; the basic region N-terminal to the first amphipathic helix mediates high-affinity DNA-binding; there are several groups of HLH proteins: those (E12/E47) which bind specific hexanucleotide sequences such as E-box (5-CANNTG-3) or StRE 5-ATCACCCCAC-3), those lacking the basic domain (Emc, Id) function as negative regulators since they fail to bind DNA, those (hairy, E(spl), deadpan) which repress transcription although they can bind specific hexanucleotide sequences such as N-box (5-CACGc/aG-3), those which have a COE domain (Collier/Olf-1/EBF) which is involved in both in dimerization and in DNA binding, and those which bind pentanucleotides ACGTG or GCGTG and have a PAS domain which allows the dimerization between PAS proteins, the binding of small molecules (e.g., dioxin), and interactions with non-PAS proteins. Length = 60
; InterPro: IPR011598 The helix-loop-helix (HLH) DNA-binding domain consists of a closed bundle of four helices in a left-handed twist with two crossover connections. The HLH domain directs dimerisation, and is juxtaposed to basic regions to create a DNA interaction interface surface that recognises specific DNA sequences. Basic region/HLH (bHLH) proteins regulate diverse biological pathways []. bHLH proteins include MyoD [], SREBPs (sterol regulatory element binding proteins) [], and yeast Pho4 (phosphatase system) []. In certain proteins the bHLH domain contains a leucine-zipper motif. The bHLH/leucine zipper (bHLHZip) domain specifies dimerisation within a network of proteins and determines sequence-specific DNA binding []. bHLHZip domains occur in the transcription factors Myc, Mad, Max and Usf [, ]. This entry is bHLHZip, which covers the bHLH domain and the leucine zipper motif, when present.; PDB: 1NLW_A 1NKP_D 1A93_A 2A93_A 1AM9_C 3U5V_A 1A0A_B 2QL2_C 1UKL_C 1AN4_B ....
A DNA-binding basic region is followed by two alpha-helices separated by a variable loop region; HLH forms homo- and heterodimers, dimerization creates a parallel, left-handed, four helix bundle; the basic region N-terminal to the first amphipathic helix mediates high-affinity DNA-binding; there are several groups of HLH proteins: those (E12/E47) which bind specific hexanucleotide sequences such as E-box (5-CANNTG-3) or StRE 5-ATCACCCCAC-3), those lacking the basic domain (Emc, Id) function as negative regulators since they fail to bind DNA, those (hairy, E(spl), deadpan) which repress transcription although they can bind specific hexanucleotide sequences such as N-box (5-CACGc/aG-3), those which have a COE domain (Collier/Olf-1/EBF) which is involved in both in dimerization and in DNA binding, and those which bind pentanucleotides ACGTG or GCGTG and
Crystal Structure Of The Heterodimeric Clock:bmal1
7e-05
>pdb|4H10|B Chain B, Intermolecular Recognition Revealed By The Complex Structure Of Human Clock-bmal1 Basic Helix-loop-helix Domains With E-box Dna Length = 71
>pdb|4H10|A Chain A, Intermolecular Recognition Revealed By The Complex Structure Of Human Clock-bmal1 Basic Helix-loop-helix Domains With E-box Dna Length = 73