Product: GRP78 Antibody
Catalog: AF0729
Description: Rabbit polyclonal antibody to GRP78
Application: WB IHC IF/ICC
Reactivity: Human, Mouse, Rat, Monkey
Prediction: Rabbit
Mol.Wt.: 60~100 kDa; 72kD(Calculated).
Uniprot: P11021
RRID: AB_2833026

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 100ul $280 In stock
 200ul $350 In stock

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Product Info

WB 1:500-1:2000, IHC 1:50-1:200, IF/ICC 1:100-1:500
*The optimal dilutions should be determined by the end user.

WB: For western blot detection of denatured protein samples. IHC: For immunohistochemical detection of paraffin sections (IHC-p) or frozen sections (IHC-f) of tissue samples. IF/ICC: For immunofluorescence detection of cell samples. ELISA(peptide): For ELISA detection of antigenic peptide.

GRP78 Antibody detects endogenous levels of total GRP78.
Cite Format: Affinity Biosciences Cat# AF0729, RRID:AB_2833026.
The antiserum was purified by peptide affinity chromatography using SulfoLink™ Coupling Resin (Thermo Fisher Scientific).
Rabbit IgG in phosphate buffered saline , pH 7.4, 150mM NaCl, 0.02% sodium azide and 50% glycerol. Store at -20 °C. Stable for 12 months from date of receipt.


78 kDa glucose regulated protein; 78 kDa glucose-regulated protein; AL022860; AU019543; BIP; D2Wsu141e; D2Wsu17e; Endoplasmic reticulum lumenal Ca(2+)-binding protein grp78; Endoplasmic reticulum lumenal Ca2+ binding protein grp78; Epididymis secretory sperm binding protein Li 89n; FLJ26106; Glucose Regulated Protein 78kDa; GRP 78; GRP-78; GRP78; GRP78_HUMAN; Heat shock 70 kDa protein 5; Heat Shock 70kDa Protein 5; Heat shock protein family A (Hsp70) member 5; HEL S 89n; Hsce70; HSPA 5; HSPA5; Immunoglobulin Heavy Chain Binding Protein; Immunoglobulin heavy chain-binding protein; mBiP; MIF2; Sez7;


GRP78 a member of the HSP family of molecular chaperones required for endoplasmic reticulum integrity and stress-induced autophagy. Plays a central role in regulating the unfolded protein response (UPR), and is an obligatory component of autophagy in mammalian cells.. May play an important role in cellular adaptation and oncogenic survival. One of the client proteins of GRP78 is protein double-stranded RNA-activated protein-like endoplasmic reticulum kinase (PERK).



Score>80(red) has high confidence and is suggested to be used for WB detection. *The prediction model is mainly based on the alignment of immunogen sequences, the results are for reference only, not as the basis of quality assurance.

Model Confidence:
High(score>80) Medium(80>score>50) Low(score<50) No confidence

PTMs - P11021 As Substrate

Site PTM Type Enzyme
S4 Phosphorylation
S14 Phosphorylation
T37 Phosphorylation
Y39 Phosphorylation
R60 Methylation
S64 Phosphorylation
Y65 Phosphorylation
T69 O-Glycosylation
T69 Phosphorylation
K81 Ubiquitination
T85 Phosphorylation
S86 Phosphorylation
T91 Phosphorylation
K96 Acetylation
K96 Ubiquitination
S107 Phosphorylation
K113 Acetylation
K113 Ubiquitination
K118 Acetylation
K118 Ubiquitination
K122 Acetylation
K123 Acetylation
K123 Ubiquitination
K125 Acetylation
K125 Ubiquitination
Y127 Phosphorylation
K138 Acetylation
K138 Ubiquitination
T139 Phosphorylation
S146 Phosphorylation
K152 Acetylation
K152 Ubiquitination
K154 Acetylation
K154 Ubiquitination
Y160 Phosphorylation
K163 Acetylation
K163 Ubiquitination
K164 Ubiquitination
Y175 Phosphorylation
K185 Ubiquitination
T189 Phosphorylation
R197 Methylation
T203 O-Glycosylation
T203 Phosphorylation
Y209 Phosphorylation
K213 Ubiquitination
T229 Phosphorylation P11021 (HSPA5)
K268 Acetylation
K268 Methylation
K268 Ubiquitination
S311 Phosphorylation
Y313 Phosphorylation
S319 Phosphorylation
K326 Acetylation
K326 Ubiquitination
K340 Acetylation
K340 Ubiquitination
K344 Ubiquitination
K352 Acetylation
K352 Sumoylation
K352 Ubiquitination
K353 Acetylation
K353 Sumoylation
K353 Ubiquitination
S354 Phosphorylation
S365 Phosphorylation
T366 Phosphorylation
K370 Ubiquitination
K376 Acetylation
K376 Ubiquitination
K382 Ubiquitination
T441 Phosphorylation
K447 Ubiquitination
S448 Phosphorylation
S452 Phosphorylation
T453 Phosphorylation
S455 Phosphorylation
T460 Phosphorylation
K464 Ubiquitination
Y466 Phosphorylation
K474 Ubiquitination
T485 Phosphorylation
R492 Methylation
T518 Phosphorylation
K523 Ubiquitination
T525 Phosphorylation
T527 Phosphorylation
K547 Acetylation
K547 Ubiquitination
S567 Phosphorylation
Y568 Phosphorylation
Y570 Phosphorylation
S571 Phosphorylation
K573 Ubiquitination
K579 Acetylation
K581 Methylation
K585 Acetylation
K585 Methylation
K585 Ubiquitination
S587 Phosphorylation
S588 Phosphorylation
K591 Methylation
K596 Methylation
K601 Acetylation
K601 Ubiquitination
S607 Phosphorylation
K617 Acetylation
K617 Ubiquitination
K619 Acetylation
S632 Phosphorylation
K633 Acetylation
K633 Ubiquitination
Y635 Phosphorylation
S637 Phosphorylation
T643 O-Glycosylation
T643 Phosphorylation
T648 Phosphorylation
K651 Acetylation

PTMs - P11021 As Enzyme

Substrate Site Source
P11021 (HSPA5) T229 Uniprot

Research Backgrounds


Endoplasmic reticulum chaperone that plays a key role in protein folding and quality control in the endoplasmic reticulum lumen. Involved in the correct folding of proteins and degradation of misfolded proteins via its interaction with DNAJC10/ERdj5, probably to facilitate the release of DNAJC10/ERdj5 from its substrate (By similarity). Acts as a key repressor of the ERN1/IRE1-mediated unfolded protein response (UPR). In the unstressed endoplasmic reticulum, recruited by DNAJB9/ERdj4 to the luminal region of ERN1/IRE1, leading to disrupt the dimerization of ERN1/IRE1, thereby inactivating ERN1/IRE1 (By similarity). Accumulation of misfolded protein in the endoplasmic reticulum causes release of HSPA5/BiP from ERN1/IRE1, allowing homodimerization and subsequent activation of ERN1/IRE1 (By similarity). Plays an auxiliary role in post-translational transport of small presecretory proteins across endoplasmic reticulum (ER). May function as an allosteric modulator for SEC61 channel-forming translocon complex, likely cooperating with SEC62 to enable the productive insertion of these precursors into SEC61 channel. Appears to specifically regulate translocation of precursors having inhibitory residues in their mature region that weaken channel gating.


AMPylated by FICD. In unstressed cells, AMPylation at Thr-518 by FICD inactivates the chaperome activity: AMPylated form is locked in a relatively inert state and only weakly stimulated by J domain-containing proteins (By similarity). In response to endoplasmic reticulum stress, de-AMPylation by the same protein, FICD, restores the chaperone activity (By similarity).

Subcellular Location:

Endoplasmic reticulum lumen. Melanosome. Cytoplasm.
Note: Identified by mass spectrometry in melanosome fractions from stage I to stage IV.

Extracellular region or secreted Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi apparatus Nucleus Mitochondrion Manual annotation Automatic computational assertionSubcellular location
Subunit Structure:

Monomer and homooligomer; homooligomerization via the interdomain linker inactivates the chaperone activity and acts as a storage of HSPA5/BiP molecules (By similarity). Interacts with DNAJC1 (via J domain) (By similarity). Component of an EIF2 complex at least composed of CELF1/CUGBP1, CALR, CALR3, EIF2S1, EIF2S2, HSP90B1 and HSPA5 (By similarity). Part of a large chaperone multiprotein complex comprising DNAJB11, HSP90B1, HSPA5, HYOU, PDIA2, PDIA4, PDIA6, PPIB, SDF2L1, UGT1A1 and very small amounts of ERP29, but not, or at very low levels, CALR nor CANX (By similarity). Interacts with TMEM132A and TRIM21. May form a complex with ERLEC1, OS9, SEL1L and SYVN1. Interacts with DNAJC10. Interacts with DNAJB9/ERdj4; leading to recruit HSPA5/BiP to ERN1/IRE1 (By similarity). Interacts with ERN1/IRE1; interaction takes place following interaction with DNAJB9/ERdj4 and leads to inactivate ERN1/IRE1 (By similarity). Interacts with MX1 (By similarity). Interacts with METTL23. Interacts with CEMIP; the interaction induces calcium leakage from the endoplasmic reticulum and cell migration. Interacts with PCSK4 form; the interaction takes place in the endoplasmic reticulum. Interacts with CIPC. Interacts with CCDC88B (via C-terminus); the interaction opposes ERN1-mediated JNK activation, protecting against apoptosis. Interacts with INPP5K; necessary for INPP5K localization at the endoplasmic reticulum. Interacts with MANF; the interaction is direct. Interacts with LOXL2; leading to activate the ERN1/IRE1-XBP1 pathway of the unfolded protein response. Interacts with CLU under stressed condition; interaction increases CLU protein stability; facilitates its retrotranslocation and redistribution to the mitochondria; cooperatively suppress stress-induced apoptosis by stabilizing mitochondrial membrane integrity. Interacts with CCDC47 (By similarity).


The interdomain linker regulates the chaperone activity by mediating the formation of homooligomers. Homooligomers are formed by engagement of the interdomain linker of one HSPA5/BiP molecule as a typical substrate of an adjacent HSPA5/BiP molecule. HSPA5/BiP oligomerization inactivates participating HSPA5/BiP protomers. HSPA5/BiP oligomers probably act as reservoirs to store HSPA5/BiP molecules when they are not needed by the cell. When the levels of unfolded proteins rise, cells can rapidly break up these oligomers to make active monomers.

Belongs to the heat shock protein 70 family.

Research Fields

· Genetic Information Processing > Folding, sorting and degradation > Protein export.

· Genetic Information Processing > Folding, sorting and degradation > Protein processing in endoplasmic reticulum.   (View pathway)

· Human Diseases > Neurodegenerative diseases > Prion diseases.

· Organismal Systems > Immune system > Antigen processing and presentation.   (View pathway)

· Organismal Systems > Endocrine system > Thyroid hormone synthesis.


1). Zonisamide, an antiepileptic drug, alleviates diabetic cardiomyopathy by inhibiting endoplasmic reticulum stress. Acta Pharmacologica Sinica, 2020 (PubMed: 32647341) [IF=8.2]

Application: WB    Species: mice    Sample: NRCMs

Fig. 6 Zonisamide alleviates HG-induced cardiac hypertrophy and apoptosis in cultured primary neonatal rat cardiomyocytes (NRCMs) via suppression of activated ER stress. NRCMs were pretreated with 5 mM 4-PBA (an inhibitor of ERS) or 10 ng/mL tunicamycin (Tm, an ERS inducer) for 2 h and then exposed to glucose (33 mM) in the presence or absence of ZNS (3 μM) for 24 h. a–b Representative and quantitative images showing the protein expression of ERS markers, including GRP78, XBP-1s, ATF6, p-PERK, PERK, ATF4, CHOP, and Hrd1. c Immunofluorescence staining of cardiomyocytes with phalloidin (red) and cell nuclei with DAPI (blue), Scale bar = 50 μm. d Quantitative analysis of cell surface area by ImageJ software. e–f Representative Western blotting and analysis of Bax and Bcl-2 expression. g–h Representative and quantitative images of GRP78, ATF6, p-PERK, PERK, ATF4, and CHOP expression. All values are the fold changes normalized to their control group. The results are presented as the means ± SEM (n = 6). *P < 0.05, **P < 0.01 vs. Con; #P < 0.05, ##P < 0.01 vs. HG; $P < 0.05, $$P < 0.01 vs. HG + ZNS.

2). Modulating endoplasmic reticulum stress in APP/PS1 mice by Gomisin B and Osthole in Bushen-Yizhi formula: Synergistic effects and therapeutic implications for Alzheimer's disease. Phytomedicine, 2023 (PubMed: 37586159) [IF=7.9]

3). Network-based identification and mechanism exploration of active ingredients against Alzheimer's disease via targeting endoplasmic reticulum stress from traditional chinese medicine. Computational and structural biotechnology journal, 2024 (PubMed: 38261917) [IF=6.0]

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