LTF

Protein identityUniProt · HPA

UniProt accession

P02788

Gene

LTF

Ensembl

ENSG00000012223

Chromosome

3

Canonical length

710 aa

Protein class

Cancer-related genes, Plasma proteins, Predicted intracellular proteins, Predicted secreted proteins

Secretome location

Secreted to blood

OverviewNCBI Gene

This gene is a member of the transferrin family of genes and its protein product is found in the secondary granules of neutrophils. The protein is a major iron-binding protein in milk and body secretions with an antimicrobial activity, making it an important component of the non-specific immune system. The protein demonstrates a broad spectrum of properties, including regulation of iron homeostasis, host defense against a broad range of microbial infections, anti-inflammatory activity, regulation of cellular growth and differentiation and protection against cancer development and metastasis. Antimicrobial, antiviral, antifungal and antiparasitic activity has been found for this protein and its peptides. Activity against both DNA and RNA viruses has been found, including activity against SARS-CoV-2, and HIV. [provided by RefSeq, Jul 2021]

Canonical amino-acid sequenceUniProt

710 residues, UniProt reviewed canonical sequence.

>P02788|LTF
     1  MKLVFLVLLF LGALGLCLAG RRRSVQWCAV SQPEATKCFQ WQRNMRKVRG PPVSCIKRDS
    61  PIQCIQAIAE NRADAVTLDG GFIYEAGLAP YKLRPVAAEV YGTERQPRTH YYAVAVVKKG
   121  GSFQLNELQG LKSCHTGLRR TAGWNVPIGT LRPFLNWTGP PEPIEAAVAR FFSASCVPGA
   181  DKGQFPNLCR LCAGTGENKC AFSSQEPYFS YSGAFKCLRD GAGDVAFIRE STVFEDLSDE
   241  AERDEYELLC PDNTRKPVDK FKDCHLARVP SHAVVARSVN GKEDAIWNLL RQAQEKFGKD
   301  KSPKFQLFGS PSGQKDLLFK DSAIGFSRVP PRIDSGLYLG SGYFTAIQNL RKSEEEVAAR
   361  RARVVWCAVG EQELRKCNQW SGLSEGSVTC SSASTTEDCI ALVLKGEADA MSLDGGYVYT
   421  AGKCGLVPVL AENYKSQQSS DPDPNCVDRP VEGYLAVAVV RRSDTSLTWN SVKGKKSCHT
   481  AVDRTAGWNI PMGLLFNQTG SCKFDEYFSQ SCAPGSDPRS NLCALCIGDE QGENKCVPNS
   541  NERYYGYTGA FRCLAENAGD VAFVKDVTVL QNTDGNNNEA WAKDLKLADF ALLCLDGKRK
   601  PVTEARSCHL AMAPNHAVVS RMDKVERLKQ VLLHQQAKFG RNGSDCPDKF CLFQSETKNL
   661  LFNDNTECLA RLHGKTTYEK YLGPQYVAGI TNLKKCSTSP LLEACEFLRK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against LTF 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

Secreted

Secreted

Yes

Transmembrane segments

0

Mean surface accessibility (rSASA)

0.23

Highest tissue expression

4,021 nTPM

Expression across tissuesHPA

ReferencesPubMed · IEDB

Publications for LTF from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)

1.16

gnomAD pLI

0

gnomAD missense Z

-0.23

DepMap mean gene effect

-0.28

DepMap dependency class

selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

• antibacterial humoral response
• antifungal humoral response
• antimicrobial humoral immune response mediated by antimicrobial peptide
• bone morphogenesis
• defense response to Gram-negative bacterium
• host-mediated suppression of viral proces
• humoral immune response
• innate immune response in mucosa
• iron ion transport
• killing of cells of another organism
• negative regulation of apoptotic process
• negative regulation of ATP-dependent activity
• negative regulation of lipopolysaccharide-mediated signaling pathway
• negative regulation of osteoclast development
• negative regulation of single-species biofilm formation in or on host organism
• negative regulation of viral genome replication
• negative regulation of viral process
• ossification
• positive regulation of bone mineralization involved in bone maturation
• positive regulation of canonical NF-kappaB signal transduction
• positive regulation of chondrocyte proliferation
• positive regulation of NF-kappaB transcription factor activity
• positive regulation of osteoblast differentiation
• positive regulation of osteoblast proliferation
• positive regulation of protein serine/threonine kinase activity
• positive regulation of toll-like receptor 4 signaling pathway
• proteolysis
• regulation of cytokine production
• regulation of tumor necrosis factor production
• negative regulation of tumor necrosis factor (ligand) superfamily member 11 production

Molecular functions

• cysteine-type endopeptidase inhibitor activity
• DNA binding
• heparin binding
• iron ion binding
• lipopolysaccharide binding
• membrane destabilizing activity
• protein serine/threonine kinase activator activity
• serine-type endopeptidase activity

Cellular components

• cell surface
• cytoplasm
• early endosome
• extracellular exosome
• extracellular region
• extracellular space
• nucleus
• phagocytic vesicle lumen
• plasma membrane
• protein-containing complex
• recycling endosome
• secretory granule
• specific granule
• specific granule lumen
• tertiary granule lumen

Protein domainsUniProt · Pfam · InterPro

• Transferrin-like domain
• Transferrin
• Transferrin family, iron binding site
• Transferrin
• Lactotransferrin

KeywordsUniProt

• Alternative promoter usage
• Antibiotic
• Antimicrobial
• Cytoplasm
• Disulfide bond
• DNA-binding
• Glycoprotein
• Heparin-binding
• Hydrolase
• Immunity
• Ion transport
• Iron
• Iron transport
• Isopeptide bond
• Metal-binding
• Nucleus
• Osteogenesis
• Protease
• Repeat
• Secreted
• Serine protease
• Signal
• Transcription
• Transcription regulation
• Transport
• Ubl conjugation

InteractionsUniProt · HPA

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

• CP
• EPPIN