DFFB

Protein identityUniProt · HPA

UniProt accession

O76075

Gene

DFFB

Ensembl

ENSG00000169598

Chromosome

1

Canonical length

338 aa

Protein class

Predicted intracellular proteins

Subcellular location

Nucleoplasm,Nucleoli

OverviewNCBI Gene

Apoptosis is a cell death process that removes toxic and/or useless cells during mammalian development. The apoptotic process is accompanied by shrinkage and fragmentation of the cells and nuclei and degradation of the chromosomal DNA into nucleosomal units. DNA fragmentation factor (DFF) is a heterodimeric protein of 40-kD (DFFB) and 45-kD (DFFA) subunits. DFFA is the substrate for caspase-3 and triggers DNA fragmentation during apoptosis. DFF becomes activated when DFFA is cleaved by caspase-3. The cleaved fragments of DFFA dissociate from DFFB, the active component of DFF. DFFB has been found to trigger both DNA fragmentation and chromatin condensation during apoptosis. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene but the biological validity of some of these variants has not been determined. [provided by RefSeq, Sep 2013]

Canonical amino-acid sequenceUniProt

338 residues, UniProt reviewed canonical sequence.

>O76075|DFFB
     1  MLQKPKSVKL RALRSPRKFG VAGRSCQEVL RKGCLRFQLP ERGSRLCLYE DGTELTEDYF
    61  PSVPDNAELV LLTLGQAWQG YVSDIRRFLS AFHEPQVGLI QAAQQLLCDE QAPQRQRLLA
   121  DLLHNVSQNI AAETRAEDPP WFEGLESRFQ SKSGYLRYSC ESRIRSYLRE VSSYPSTVGA
   181  EAQEEFLRVL GSMCQRLRSM QYNGSYFDRG AKGGSRLCTP EGWFSCQGPF DMDSCLSRHS
   241  INPYSNRESR ILFSTWNLDH IIEKKRTIIP TLVEAIKEQD GREVDWEYFY GLLFTSENLK
   301  LVHIVCHKKT THKLNCDPSR IYKPQTRLKR KQPVRKRQ

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against DFFB can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability

Intracellular

Secreted

No

Transmembrane segments

0

Mean surface accessibility (rSASA)

0.32

Highest tissue expression

4.3 nTPM

Expression across tissuesHPA

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)

1.08

gnomAD pLI

0

gnomAD missense Z

0.41

DepMap mean gene effect

-0.03

DepMap dependency class

selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

• apoptotic chromosome condensation
• apoptotic DNA fragmentation
• DNA catabolic process
• negative regulation of apoptotic DNA fragmentation

Molecular functions

• DNA binding
• DNA endonuclease activity
• DNA nuclease activity
• enzyme binding
• hydrolase activity
• identical protein binding

Cellular components

• chromatin
• cytosol
• nucleolus
• nucleoplasm
• nucleus
• protein-containing complex

Protein domainsUniProt · Pfam · InterPro

• CIDE-N domain
• His-Me finger superfamily
• CIDE-N domain
• DNA fragmentation factor 40, C-terminal
• DNA fragmentation factor 40
• DNA fragmentation factor 40 kDa

KeywordsUniProt

• Apoptosis
• Cytoplasm
• Hydrolase
• Nuclease
• Nucleus

InteractionsUniProt · HPA

Protein binding partners of DFFB in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• H1-1
• CIDEB
• DFFA