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Monoclonal Anti-HA antibody produced in mouse


Antibody ID


Target Antigen

HA antibody produced in mouse ha, hamster



Cat Num


Proper Citation

(Sigma-Aldrich Cat# H3663, RRID:AB_262051)


monoclonal antibody

Host Organism


Analysis of Drosophila STING Reveals an Evolutionarily Conserved Antimicrobial Function.

  • Martin M
  • Cell Rep
  • 2018 Jun 19

Literature context: al anti-HA Sigma-Aldrich H3663; RRID:AB_262051 Rabbit polyclonal anti-actin Si


The vertebrate protein STING, an intracellular sensor of cyclic dinucleotides, is critical to the innate immune response and the induction of type I interferon during pathogenic infection. Here, we show that a STING ortholog (dmSTING) exists in Drosophila, which, similar to vertebrate STING, associates with cyclic dinucleotides to initiate an innate immune response. Following infection with Listeria monocytogenes, dmSTING activates an innate immune response via activation of the NF-κB transcription factor Relish, part of the immune deficiency (IMD) pathway. DmSTING-mediated activation of the immune response reduces the levels of Listeria-induced lethality and bacterial load in the host. Of significance, dmSTING triggers an innate immune response in the absence of a known functional cyclic guanosine monophosphate (GMP)-AMP synthase (cGAS) ortholog in the fly. Together, our results demonstrate that STING is an evolutionarily conserved antimicrobial effector between flies and mammals, and it comprises a key component of host defense against pathogenic infection in Drosophila.

Funding information:
  • NIA NIH HHS - R01 AG040061-01A1(United States)
  • NIAID NIH HHS - K99 AI106963()
  • NIAID NIH HHS - R00 AI106963()
  • NIAID NIH HHS - R21 AI128103()

Host Nitric Oxide Disrupts Microbial Cell-to-Cell Communication to Inhibit Staphylococcal Virulence.

  • Urbano R
  • Cell Host Microbe
  • 2018 May 9

Literature context: l HA-7 Sigma-Aldrich Cat#H3663; RRID:AB_262051 7B8 monoclonal antibody to α-to


Staphylococcus aureus is a commensal bacterium that can asymptomatically colonize its host but also causes invasive infections. Quorum sensing regulates S. aureus virulence and the transition from a commensal to a pathogenic organism. However, little is known about how host innate immunity affects interbacterial communication. We show that nitric oxide suppresses staphylococcal virulence by targeting the Agr quorum sensing system. Nitric oxide-mediated inhibition occurs through direct modification of cysteine residues C55, C123, and C199 of the AgrA transcription factor. Cysteine modification decreases AgrA promoter occupancy as well as transcription of the agr operon and quorum sensing-activated toxin genes. In a staphylococcal pneumonia model, mice lacking inducible nitric oxide synthase develop more severe disease with heightened mortality and proinflammatory cytokine responses. In addition, staphylococcal α-toxin production increases in the absence of nitric oxide or nitric oxide-sensitive AgrA cysteine residues. Our findings demonstrate an anti-virulence mechanism for nitric oxide in innate immunity.

Funding information:
  • NIAID NIH HHS - AI-AI30162(United States)
  • NIAID NIH HHS - R01 AI039557()
  • NIAID NIH HHS - R01 AI123124()
  • NIAID NIH HHS - T32 AI055396()

A Dendritic Guidance Receptor Complex Brings Together Distinct Actin Regulators to Drive Efficient F-Actin Assembly and Branching.

  • Zou W
  • Dev. Cell
  • 2018 May 7

Literature context: ouse anti-HA Sigma Cat#: H3663; RRID:AB_262051 Rabbit anti-MYC Santa Cruz Biot


Proper morphogenesis of dendrites plays a fundamental role in the establishment of neural circuits. The molecular mechanism by which dendrites grow highly complex branches is not well understood. Here, using the Caenorhabditis elegans PVD neuron, we demonstrate that high-order dendritic branching requires actin polymerization driven by coordinated interactions between two membrane proteins, DMA-1 and HPO-30, with their cytoplasmic interactors, the RacGEF TIAM-1 and the actin nucleation promotion factor WAVE regulatory complex (WRC). The dendrite branching receptor DMA-1 directly binds to the PDZ domain of TIAM-1, while the claudin-like protein HPO-30 directly interacts with the WRC. On dendrites, DMA-1 and HPO-30 form a receptor-associated signaling complex to bring TIAM-1 and the WRC to close proximity, leading to elevated assembly of F-actin needed to drive high-order dendrite branching. The synergistic activation of F-actin assembly by scaffolding distinct actin regulators might represent a general mechanism in promoting complex dendrite arborization.

Funding information:
  • Canadian Institutes of Health Research - MOP-74650(Canada)

Boosting ATM activity alleviates aging and extends lifespan in a mouse model of progeria.

  • Qian M
  • Elife
  • 2018 May 2

Literature context: dy HA Sigma-Aldrich Cat# H3663; RRID:AB_262051 Applications: WB


DNA damage accumulates with age (Lombard et al., 2005). However, whether and how robust DNA repair machinery promotes longevity is elusive. Here, we demonstrate that ATM-centered DNA damage response (DDR) progressively declines with senescence and age, while low dose of chloroquine (CQ) activates ATM, promotes DNA damage clearance, rescues age-related metabolic shift, and prolongs replicative lifespan. Molecularly, ATM phosphorylates SIRT6 deacetylase and thus prevents MDM2-mediated ubiquitination and proteasomal degradation. Extra copies of Sirt6 extend lifespan in Atm-/- mice, with restored metabolic homeostasis. Moreover, the treatment with CQ remarkably extends lifespan of Caenorhabditis elegans, but not the ATM-1 mutants. In a progeria mouse model with low DNA repair capacity, long-term administration of CQ ameliorates premature aging features and extends lifespan. Thus, our data highlights a pro-longevity role of ATM, for the first time establishing direct causal links between robust DNA repair machinery and longevity, and providing therapeutic strategy for progeria and age-related metabolic diseases.

Funding information:
  • Department of Health - (United Kingdom)
  • Ministry of Science and Technology of the People's Republic of China - 2016YFC0904600()
  • Ministry of Science and Technology of the People's Republic of China - 2017YFA0503900()
  • National Natural Science Foundation of China - 81422016()
  • National Natural Science Foundation of China - 81501206()
  • National Natural Science Foundation of China - 81501210()
  • National Natural Science Foundation of China - 81571374()
  • National Natural Science Foundation of China - 91439133()
  • Natural Science Foundation of Guangdong Province - 2014A030308011()
  • Natural Science Foundation of Guangdong Province - 2015A030308007()
  • Natural Science Foundation of Guangdong Province - 2016A030310064()
  • Research Grant Council of Hong Kong - 773313()
  • Research Grant Council of Hong Kong - HKU2/CRF/13G()
  • Shenzhen Science and Technology Innovation Commission - CXZZ20140903103747568()
  • Shenzhen Science and Technology Innovation Commission - JCYJ20140418095735645()
  • Shenzhen Science and Technology Innovation Commission - JCYJ20160226191451487()

A Potent and Specific CD38 Inhibitor Ameliorates Age-Related Metabolic Dysfunction by Reversing Tissue NAD+ Decline.

  • Tarragó MG
  • Cell Metab.
  • 2018 May 1

Literature context: HA Sigma AbH3663; RRID:AB_262051 Flag Sigma AbF1804; RRID: AB_26


Aging is characterized by the development of metabolic dysfunction and frailty. Recent studies show that a reduction in nicotinamide adenine dinucleotide (NAD+) is a key factor for the development of age-associated metabolic decline. We recently demonstrated that the NADase CD38 has a central role in age-related NAD+ decline. Here we show that a highly potent and specific thiazoloquin(az)olin(on)e CD38 inhibitor, 78c, reverses age-related NAD+ decline and improves several physiological and metabolic parameters of aging, including glucose tolerance, muscle function, exercise capacity, and cardiac function in mouse models of natural and accelerated aging. The physiological effects of 78c depend on tissue NAD+ levels and were reversed by inhibition of NAD+ synthesis. 78c increased NAD+ levels, resulting in activation of pro-longevity and health span-related factors, including sirtuins, AMPK, and PARPs. Furthermore, in animals treated with 78c we observed inhibition of pathways that negatively affect health span, such as mTOR-S6K and ERK, and attenuation of telomere-associated DNA damage, a marker of cellular aging. Together, our results detail a novel pharmacological strategy for prevention and/or reversal of age-related NAD+ decline and subsequent metabolic dysfunction.

Funding information:
  • NHLBI NIH HHS - N01-HV-28186(United States)

Injury Activates Ca2+/Calmodulin-Dependent Phosphorylation of JAV1-JAZ8-WRKY51 Complex for Jasmonate Biosynthesis.

  • Yan C
  • Mol. Cell
  • 2018 Apr 5

Literature context: nti-HA Sigma-Aldrich Cat#H3663; RRID:AB_262051 Mouse monoclonal anti-myc Abmar


Insect herbivory causes severe damage to plants and threatens the world's food production. During evolutionary adaptation, plants have evolved sophisticated mechanisms to rapidly accumulate a key defense hormone, jasmonate (JA), that triggers plant defense against herbivory. However, little is known about how plants initially activate JA biosynthesis at encounter with herbivory. Here, we uncover that a novel JAV1-JAZ8-WRKY51 (JJW) complex controls JA biosynthesis to defend against insect attack. In healthy plants, the JJW complex represses JA biosynthesis to restrain JA at a low basal level to ensure proper plant growth. When plants are injured by insect attack, injury rapidly triggers calcium influxes to activate calmodulin-dependent phosphorylation of JAV1, which disintegrates JJW complex and activates JA biosynthesis, giving rise to the rapid burst of JA for plant defense. Our findings offer new insights into the highly sophisticated defense systems evolved by plants to defend against herbivory.

Funding information:
  • NIGMS NIH HHS - R01 GM-66190(United States)

Prp19/Pso4 Is an Autoinhibited Ubiquitin Ligase Activated by Stepwise Assembly of Three Splicing Factors.

  • de Moura TR
  • Mol. Cell
  • 2018 Mar 15

Literature context: ; RRID:AB_262051 Anti-FLAG (M2) Sigma-Aldrich Ca


Human nineteen complex (NTC) acts as a multimeric E3 ubiquitin ligase in DNA repair and splicing. The transfer of ubiquitin is mediated by Prp19-a homotetrameric component of NTC whose elongated coiled coils serve as an assembly axis for two other proteins called SPF27 and CDC5L. We find that Prp19 is inactive on its own and have elucidated the structural basis of its autoinhibition by crystallography and mutational analysis. Formation of the NTC core by stepwise assembly of SPF27, CDC5L, and PLRG1 onto the Prp19 tetramer enables ubiquitin ligation. Protein-protein crosslinking of NTC, functional assays in vitro, and assessment of its role in DNA damage response provide mechanistic insight into the organization of the NTC core and the communication between PLRG1 and Prp19 that enables E3 activity. This reveals a unique mode of regulation for a complex E3 ligase and advances understanding of its dynamics in various cellular pathways.

Funding information:
  • Department of Health - II-FS-0109-11028(United Kingdom)

Electron Cryo-microscopy Structure of Ebola Virus Nucleoprotein Reveals a Mechanism for Nucleocapsid-like Assembly.

  • Su Z
  • Cell
  • 2018 Feb 22

Literature context: anti-HA Sigma Cat#H3663 RRID# AB_262051 Anti-tubulin Sigma Cat#T8328 RR


Ebola virus nucleoprotein (eNP) assembles into higher-ordered structures that form the viral nucleocapsid (NC) and serve as the scaffold for viral RNA synthesis. However, molecular insights into the NC assembly process are lacking. Using a hybrid approach, we characterized the NC-like assembly of eNP, identified novel regulatory elements, and described how these elements impact function. We generated a three-dimensional structure of the eNP NC-like assembly at 5.8 Å using electron cryo-microscopy and identified a new regulatory role for eNP helices α22-α23. Biochemical, biophysical, and mutational analyses revealed that inter-eNP contacts within α22-α23 are critical for viral NC assembly and regulate viral RNA synthesis. These observations suggest that the N terminus and α22-α23 of eNP function as context-dependent regulatory modules (CDRMs). Our current study provides a framework for a structural mechanism for NC-like assembly and a new therapeutic target.

Funding information:
  • NCI NIH HHS - T32CA09361(United States)
  • NIAID NIH HHS - P01 AI120943()
  • NIAID NIH HHS - R01 AI123926()
  • NIAID NIH HHS - U19 AI109664()
  • NIGMS NIH HHS - P41 GM103422()
  • NIGMS NIH HHS - P41 GM103832()
  • NIGMS NIH HHS - R01 GM080139()
  • NIGMS NIH HHS - R01 GM124007()

MPK3- and MPK6-Mediated ICE1 Phosphorylation Negatively Regulates ICE1 Stability and Freezing Tolerance in Arabidopsis.

  • Li H
  • Dev. Cell
  • 2017 Dec 4

Literature context: Aldrich Cat#H3663; RRID:AB_262051 Mouse monoclonal anti-GST Beiji


Low temperatures affect plant growth, development, productivity, and ecological distribution. Expression of the C-repeat-binding factor (CBF) transcription factors is induced by cold stress, which in turn activates downstream cold-responsive (COR) genes that are required for the acquisition of freezing tolerance. Inducer of CBF expression 1 (ICE1) is a master regulator of CBFs, and ICE1 stability is crucial for its function. However, the regulation of ICE1 is not well understood. Here, we report that mitogen-activated protein kinase 3 (MPK3) and MPK6 interact with and phosphorylate ICE1, which reduces its stability and transcriptional activity. Consistently, the mpk3 and mpk6 single mutants and the mpk3 mpk6 double mutants show enhanced freezing tolerance, whereas MPK3/MPK6 activation attenuates freezing tolerance. Phosphor-inactive mutations of ICE1 complement freezing sensitivity in the ice1-2 mutant. These combined results indicate that MPK3/MPK6 phosphorylate and destabilize ICE1, which negatively regulates CBF expression and freezing tolerance in plants.

Funding information:
  • Intramural NIH HHS - Z01 HL005801-05(United States)

OsMAPK3 Phosphorylates OsbHLH002/OsICE1 and Inhibits Its Ubiquitination to Activate OsTPP1 and Enhances Rice Chilling Tolerance.

  • Zhang Z
  • Dev. Cell
  • 2017 Dec 18

Literature context: nti-HA Sigma-Aldrich Cat#H3663; RRID:AB_262051 Mouse monoclonal anti-His TIANG


Improvement of chilling tolerance is a major target in rice breeding. The signaling pathways regulating chilling consist of complex networks, including key transcription factors and their targets. However, it remains largely unknown how transcription factors are activated by chilling stress. Here, we report that the transcription factor OsbHLH002/OsICE1 is phosphorylated by OsMAPK3 under chilling stress. The osbhlh002-1 knockout mutant and antisense transgenic plants showed chilling hypersensitivity, whereas OsbHLH002-overexpressing plants exhibited enhanced chilling tolerance. OsbHLH002 can directly target OsTPP1, which encodes a key enzyme for trehalose biosynthesis. OsMAPK3 interacts with OsbHLH002 to prevent its ubiquitination by the E3 ligase OsHOS1. Under chilling stress, active OsMAPK3 phosphorylates OsbHLH002, leading to accumulation of phospho-OsbHLH002, which promotes OsTPP1 expression and increases trehalose content and resistance to chilling damage. Taken together, these results indicate that OsbHLH002 is phosphorylated by OsMAPK3, which enhances OsbHLH002 activation to its target OsTPP1 during chilling stress.

Funding information:
  • NIGMS NIH HHS - T32 GM007198(United States)

The Plasticity of the Hsp90 Co-chaperone System.

  • Sahasrabudhe P
  • Mol. Cell
  • 2017 Sep 21

Literature context: Aldrich Catalog #: H3663; RRID:AB_262051 Mouse monoclonal anti-avian Src


The Hsp90 system in the eukaryotic cytosol is characterized by a cohort of co-chaperones that bind to Hsp90 and affect its function. Although progress has been made regarding the underlying biochemical mechanisms, how co-chaperones influence Hsp90 client proteins in vivo has remained elusive. By investigating the effect of 12 Hsp90 co-chaperones on the activity of different client proteins in yeast, we find that deletion of co-chaperones can have a neutral or negative effect on client activity but can also lead to more active clients. Only a few co-chaperones are active on all clients studied. Closely related clients and even point mutants can depend on different co-chaperones. These effects are direct because differences in client-co-chaperone interactions can be reconstituted in vitro. Interestingly, some co-chaperones affect client conformation in vivo. Thus, co-chaperones adapt the Hsp90 cycle to the requirements of the client proteins, ensuring optimal activation.

Retrograde Synaptic Inhibition Is Mediated by α-Neurexin Binding to the α2δ Subunits of N-Type Calcium Channels.

  • Tong XJ
  • Neuron
  • 2017 Jul 19

Literature context: #: H3663 (RRID:AB_262051); Clone#:


The synaptic adhesion molecules Neurexin and Neuroligin alter the development and function of synapses and are linked to autism in humans. In C. elegans, post-synaptic Neurexin (NRX-1) and pre-synaptic Neuroligin (NLG-1) mediate a retrograde synaptic signal that inhibits acetylcholine (ACh) release at neuromuscular junctions. Here, we show that the retrograde signal decreases ACh release by inhibiting the function of pre-synaptic UNC-2/CaV2 calcium channels. Post-synaptic NRX-1 binds to an auxiliary subunit of pre-synaptic UNC-2/CaV2 channels (UNC-36/α2δ), decreasing UNC-36 abundance at pre-synaptic elements. Retrograde inhibition is mediated by a soluble form of NRX-1's ectodomain, which is released from the post-synaptic membrane by the SUP-17/ADAM10 protease. Mammalian Neurexin-1α binds α2δ-3 and decreases CaV2.2 current in transfected cells, whereas Neurexin-1α has no effect on CaV2.2 reconstituted with α2δ-1 and α2δ-2. Collectively, these results suggest that α-Neurexin binding to α2δ is a conserved mechanism for regulating synaptic transmission.

Funding information:
  • NIGMS NIH HHS - R01 GM054728()
  • NINDS NIH HHS - R01 NS032196()
  • NINDS NIH HHS - R01 NS055251()

Plasma Membrane CRPK1-Mediated Phosphorylation of 14-3-3 Proteins Induces Their Nuclear Import to Fine-Tune CBF Signaling during Cold Response.

  • Liu Z
  • Mol. Cell
  • 2017 Apr 6

Literature context: monoclonal anti-HASigma-AldrichCat#H3663Mouse monoclonal anti-GFPAbmartC


In plant cells, changes in fluidity of the plasma membrane may serve as the primary sensor of cold stress; however, the precise mechanism and how the cell transduces and fine-tunes cold signals remain elusive. Here we show that the cold-activated plasma membrane protein cold-responsive protein kinase 1 (CRPK1) phosphorylates 14-3-3 proteins. The phosphorylated 14-3-3 proteins shuttle from the cytosol to the nucleus, where they interact with and destabilize the key cold-responsive C-repeat-binding factor (CBF) proteins. Consistent with this, the crpk1 and 14-3-3κλ mutants show enhanced freezing tolerance, and transgenic plants overexpressing 14-3-3λ show reduced freezing tolerance. Further study shows that CRPK1 is essential for the nuclear translocation of 14-3-3 proteins and for 14-3-3 function in freezing tolerance. Thus, our study reveals that the CRPK1-14-3-3 module transduces the cold signal from the plasma membrane to the nucleus to modulate CBF stability, which ensures a faithfully adjusted response to cold stress of plants.

Gene Resistance to Transcriptional Reprogramming following Nuclear Transfer Is Directly Mediated by Multiple Chromatin-Repressive Pathways.

  • Jullien J
  • Mol. Cell
  • 2017 Mar 2

Literature context: MA H3663; RRID:AB_262051 Rabbit ant


Understanding the mechanism of resistance of genes to reactivation will help improve the success of nuclear reprogramming. Using mouse embryonic fibroblast nuclei with normal or reduced DNA methylation in combination with chromatin modifiers able to erase H3K9me3, H3K27me3, and H2AK119ub1 from transplanted nuclei, we reveal the basis for resistance of genes to transcriptional reprogramming by oocyte factors. A majority of genes is affected by more than one type of treatment, suggesting that resistance can require repression through multiple epigenetic mechanisms. We classify resistant genes according to their sensitivity to 11 chromatin modifier combinations, revealing the existence of synergistic as well as adverse effects of chromatin modifiers on removal of resistance. We further demonstrate that the chromatin modifier USP21 reduces resistance through its H2AK119 deubiquitylation activity. Finally, we provide evidence that H2A ubiquitylation also contributes to resistance to transcriptional reprogramming in mouse nuclear transfer embryos.

NBS1 Phosphorylation Status Dictates Repair Choice of Dysfunctional Telomeres.

  • Rai R
  • Mol. Cell
  • 2017 Mar 2

Literature context: ch H3663; RRID:AB_262051 PP1-α Sant


Telomeres employ TRF2 to protect chromosome ends from activating the DNA damage sensor MRE11-RAD50-NBS1 (MRN), thereby repressing ATM-dependent DNA damage checkpoint responses. How TRF2 prevents MRN activation at dysfunctional telomeres is unclear. Here, we show that the phosphorylation status of NBS1 determines the repair pathway choice of dysfunctional telomeres. The crystal structure of the TRF2-NBS1 complex at 3.0 Å resolution shows that the NBS1 429YQLSP433 motif interacts specifically with the TRF2TRFH domain. Phosphorylation of NBS1 serine 432 by CDK2 in S/G2 dissociates NBS1 from TRF2, promoting TRF2-Apollo/SNM1B complex formation and the protection of leading-strand telomeres. Classical-NHEJ-mediated repair of telomeres lacking TRF2 requires phosphorylated NBS1S432 to activate ATM, while interaction of de-phosphorylated NBS1S432 with TRF2 promotes alternative-NHEJ repair of telomeres lacking POT1-TPP1. Our work advances understanding of how the TRF2TRFH domain orchestrates telomere end protection and reveals how the phosphorylation status of the NBS1S432 dictates repair pathway choice of dysfunctional telomeres.

Funding information:
  • NCI NIH HHS - P30 CA016359()
  • NIA NIH HHS - R01 AG028888()

Phosphorylation-Dependent Feedback Inhibition of RIG-I by DAPK1 Identified by Kinome-wide siRNA Screening.

  • Willemsen J
  • Mol. Cell
  • 2017 Feb 2

Literature context: ch H3663, RRID:AB_262051 rabbit pol


Cell-autonomous induction of type I interferon must be stringently regulated. Rapid induction is key to control virus infection, whereas proper limitation of signaling is essential to prevent immunopathology and autoimmune disease. Using unbiased kinome-wide RNAi screening followed by thorough validation, we identified 22 factors that regulate RIG-I/IRF3 signaling activity. We describe a negative-feedback mechanism targeting RIG-I activity, which is mediated by death associated protein kinase 1 (DAPK1). RIG-I signaling triggers DAPK1 kinase activation, and active DAPK1 potently inhibits RIG-I stimulated IRF3 activity and interferon-beta production. DAPK1 phosphorylates RIG-I in vitro at previously reported as well as other sites that limit 5'ppp-dsRNA sensing and virtually abrogate RIG-I activation.

Drosophila neprilysins control insulin signaling and food intake via cleavage of regulatory peptides.

  • Hallier B
  • Elife
  • 2016 Dec 6

Literature context: anti-HA (RRID:AB_262051, 1:100, ra


Insulin and IGF signaling are critical to numerous developmental and physiological processes, with perturbations being pathognomonic of various diseases, including diabetes. Although the functional roles of the respective signaling pathways have been extensively studied, the control of insulin production and release is only partially understood. Herein, we show that in Drosophila expression of insulin-like peptides is regulated by neprilysin activity. Concomitant phenotypes of altered neprilysin expression included impaired food intake, reduced body size, and characteristic changes in the metabolite composition. Ectopic expression of a catalytically inactive mutant did not elicit any of the phenotypes, which confirms abnormal peptide hydrolysis as a causative factor. A screen for corresponding substrates of the neprilysin identified distinct peptides that regulate insulin-like peptide expression, feeding behavior, or both. The high functional conservation of neprilysins and their substrates renders the characterized principles applicable to numerous species, including higher eukaryotes and humans.