STK33

Protein identityUniProt · HPA

UniProt accession

Q9BYT3

Gene

STK33

Ensembl

ENSG00000130413

Chromosome

11

Canonical length

514 aa

Protein class

Enzymes, Predicted intracellular proteins

Subcellular location

Nucleoplasm,Nucleoli,Cytosol,Flagellar centriole,Mid piece

Quaternary structure

Homodimer

OverviewNCBI Gene

Enables protein serine/threonine kinase activity. Involved in spermatogenesis. Predicted to be located in manchette. Predicted to be active in nucleus. Implicated in colorectal cancer; depressive disorder; and spermatogenic failure 93. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

514 residues, UniProt reviewed canonical sequence.

>Q9BYT3|STK33
     1  MADSGLDKKS TKCPDCSSAS QKDVLCVCSS KTRVPPVLVV EMSQTSSIGS AESLISLERK
    61  KEKNINRDIT SRKDLPSRTS NVERKASQQQ WGRGNFTEGK VPHIRIENGA AIEEIYTFGR
   121  ILGKGSFGIV IEATDKETET KWAIKKVNKE KAGSSAVKLL EREVNILKSV KHEHIIHLEQ
   181  VFETPKKMYL VMELCEDGEL KEILDRKGHF SENETRWIIQ SLASAIAYLH NNDIVHRDLK
   241  LENIMVKSSL IDDNNEINLN IKVTDFGLAV KKQSRSEAML QATCGTPIYM APEVISAHDY
   301  SQQCDIWSIG VVMYMLLRGE PPFLASSEEK LFELIRKGEL HFENAVWNSI SDCAKSVLKQ
   361  LMKVDPAHRI TAKELLDNQW LTGNKLSSVR PTNVLEMMKE WKNNPESVEE NTTEEKNKPS
   421  TEEKLKSYQP WGNVPDANYT SDEEEEKQST AYEKQFPATS KDNFDMCSSS FTSSKLLPAE
   481  IKGEMEKTPV TPSQGTATKY PAKSGALSRT KKKL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against STK33 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)

0.45

Highest tissue expression

45 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about STK33.

Disease | AllUniProt

Conditions STK33 is implicated in, by any mechanism.

• Spermatogenic failure 93 (SPGF93) MIM:620849

Disease | GeneticClinVar

1 pathogenic / likely-pathogenic of 100 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• Spermatogenic failure 93

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)

0.86

gnomAD pLI

0

gnomAD missense Z

0.49

DepMap mean gene effect

0.1

DepMap dependency class

none

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

• manchette assembly
• mitotic DNA damage checkpoint signaling
• negative regulation of proteasomal ubiquitin-dependent protein catabolic process
• negative regulation of protein polyubiquitination
• protein autophosphorylation
• spermatogenesis

Molecular functions

• ATP binding
• protein serine kinase activity
• protein serine/threonine kinase activity

Cellular components

• manchette
• nucleus
• perinuclear region of cytoplasm

Protein domainsUniProt · Pfam · InterPro

• Protein kinase domain
• Serine/threonine-protein kinase, active site
• Protein kinase-like domain superfamily
• Protein kinase, ATP binding site
• Protein kinase domain

KeywordsUniProt

• ATP-binding
• Cytoplasm
• Cytoskeleton
• Differentiation
• Kinase
• Nucleotide-binding
• Phosphoprotein
• Serine/threonine-protein kinase
• Spermatogenesis
• Transferase

InteractionsUniProt · HPA

Protein binding partners of STK33 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• VIM