• Product name

  • Description

    Rabbit polyclonal to CLK1
  • Host species

  • Specificity

    This antibody detects endogenous levels of total CLK1 protein.
  • Tested applications

    Suitable for: ELISA, WB, ICC/IFmore details
  • Species reactivity

    Reacts with: Human
    Predicted to work with: Mouse
  • Immunogen

    A synthesized peptide derived from the internal region of human CLK1.

  • Positive control

    • HUVEC cells and extracts from 293 cells.



Our Abpromise guarantee covers the use of ab74044 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
ELISA 1/5000.
WB 1/500 - 1/1000. Predicted molecular weight: 57 kDa.
ICC/IF 1/500 - 1/1000.


  • Function

    Phosphorylates serine- and arginine-rich (SR) proteins of the spliceosomal complex may be a constituent of a network of regulatory mechanisms that enable SR proteins to control RNA splicing. Phosphorylates serines, threonines and tyrosines.
  • Sequence similarities

    Belongs to the protein kinase superfamily. CMGC Ser/Thr protein kinase family. Lammer subfamily.
    Contains 1 protein kinase domain.
  • Post-translational

    Autophosphorylates on all three types of residues.
  • Cellular localization

  • Information by UniProt
  • Database links

  • Alternative names

    • CDC like kinase 1 antibody
    • CDC-like kinase 1 antibody
    • CDC28/CDC2 like kinase antibody
    • CLK antibody
    • CLK/STY antibody
    • Clk1 antibody
    • CLK1_HUMAN antibody
    • Dual specificity protein kinase CLK1 antibody
    • Protein tyrosine kinase STY antibody
    • STY antibody
    see all


  • All lanes : Anti-CLK1 antibody (ab74044) at 1/500 dilution

    Lane 1 : Extracts from 293 cells
    Lane 2 : Extracts from 293 cells with immunizing peptide at 5 µg

    Lysates/proteins at 5 µg per lane.

    Predicted band size: 57 kDa
    Observed band size: 57 kDa
    Additional bands at: 30 kDa, 34 kDa, 36 kDa. We are unsure as to the identity of these extra bands.

  • Immunofluorescence analysis of CLK1 in HUVEC cells, using ab74044 at a 1/500 dilution.
    Left image: untreated.
    Right image: treated with immunizing peptide.


This product has been referenced in:

  • Fant X  et al. cdc-like/dual-specificity tyrosine phosphorylation-regulated kinases inhibitor leucettine L41 induces mTOR-dependent autophagy: implication for Alzheimer's disease. Mol Pharmacol 85:441-50 (2014). Read more (PubMed: 24366666) »
  • Ninomiya K  et al. Stress-responsive maturation of Clk1/4 pre-mRNAs promotes phosphorylation of SR splicing factor. J Cell Biol 195:27-40 (2011). WB . Read more (PubMed: 21949414) »
See all 2 Publications for this product

Customer reviews and Q&As

1-8 of 8 Abreviews or Q&A

Western blot
Mouse Cell lysate - whole cell (3T3-L1)
Gel Running Conditions
Reduced Denaturing (12.5%)
Loading amount
20 µg
500µM IBMX, 0.5µM dexamethasone, 350nM insulin, 2µM rosiglitazone
Blocking step
Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 24°C

Abcam user community

Verified customer

Submitted Nov 05 2018

Western blot
Mouse Cell lysate - whole cell (P19 cells)
Gel Running Conditions
Non-reduced Denaturing (4 - 12 % Novex gel with Mops runing buffer)
Loading amount
30 µg
P19 cells
Blocking step
BSA as blocking agent for 6 hour(s) and 0 minute(s) · Concentration: 3% · Temperature: 4°C

Abcam user community

Verified customer

Submitted Jul 05 2016


The amino acid range I gave you before, 110 - 160, is not the ab74044 immunogen, it is just a range that contains it. The exact sequence is considered proprietary by the developer of the antibody, but I was at least able to find out that the immunogen does not include threonine 123 or serine 140, it only includes threonine 138. So, the range around the immunogen can be narrowed to aa 124 - 139.

Read More


Here is the IF protocol from the lab that validated this antibody for this application. The "polyoxymethylene" is 4% paraformaldehyde. The 24-well plates that are referred to in the protocol are either cover-slip-bottomed or contain cover-slips. Chamber slides will also work.

A. Solutions and Reagents

1. 10× PBS: To prepare 1L add 80g NaCl, 2g KCl, 2g KH2PO4and 28.5g NaHPO4to 1L water for injection. Adjust pH to 7.4.

2. 4% Polyoxymethylene: To prepare 100mL add 4g polyoxymethylene to 100mL 1×PBS. Adjust pHto 7.4.

3. 1×PBS/0.2% Triton X-100(PBS/Triton):To prepare 500mL add 1mL Triton X-100 to 500mL 1× PBS.

4. 1×PBS/3% BSA(PBS/BSA): To prepare 100mL add 3g BSA to 100mL 1× PBS.

B. Preparation Fixation permeabilization

1. Rinse cells briefly in PBS.

2. Aspirate PBS, cover cells to a depth of 2-3mm about 200ul with 4% polyoxymethylene.

3. Allow cells to fix for 15 minutes at room temperature.

4. Aspirate fixative, rinse three times in PBS for 5 minutes each.

5. Aspirate PBS, cover cells to a depth of 2-3mm about 200ul with PBS/Tritonfor 5 minutes at room temperature.

6. Aspirate permeability agent rinse three times in PBS for 5 minutes each.

C. Immunostaining

1. Gently add 200ul of primary antibody dilutedin PBS/BSAto the 24 well plates each well.

2. Incubate 60 minutes at 37℃or overnight at 4℃.

3. Aspirate diluted primary antibody, then rinse three times in PBS for 5 minutes each.

4. Incubate in fluorochrome-conjugate secondary antibody diluted in PBS/BSA to the 24 well plates 100ul each well for 30 minutes at room temperature in dark.

5. Aspirate diluted fluorochrome-conjugate secondary antibody, then rinse three times in PBS for 5 minutes each.

6. Test under fluorescence microscope.

Read More


The CLK homology information I received from our sources of the two CLK1 antibodies and the one CLK4 antibody that will be useful for western blotting of human samples is as follows. The percentages refer to percentage identity of amino acids of the antibody immunogens and the three other CLK proteins. Ab104321 anti-CLK4 CLK1: 57% CLK2: 43% CLK3: 43% CLK4: 100% ab71408 anti-CLK1 The immunogen for the CLK1 antibody showed 100% homology with CLK4 but no significant homology for CLK2 or CLK3. ab74044 anti-CLK1 The immunogen homology is 54% with human CLK2, 45% with human CLK3, 77% with CLK4. So ab74044 is likely to have more specificity for CLK1 than will ab71408, which will probably cross-react with CLK4. However, the 77% identity of the ab74044 immunogen with CLK4 is still high. Given that CLK1 and CLK4 are the same molecular weight, it will be impossible to distinguish them from one another in blots. I hope this helps at least a little. If you have any questions, please contact us.

Read More


Thank you for contacting us. I am very sorry for the confusion. I performed a BLAST to find out the percentage of homology between the four proteins, and the results are: -CLK1-CLK2: 53.5% -CLK1-CLK3: 14% -CLK1-CLK4: 77% -CLK2-CLK3: 17% -CLK2-CLK4: 55% -CLK3-CLK4: 14% We usually predict cross-reactivity when the homology between the sequences is over 85%. So, in this case, I would dare to affirm there might be some slight reactivity between CLK1 and CLK4, but the rest of proteins are very unlikely to cross react. I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

Read More


Thank you for your inquiry. Unfortunately, we do not currently have more information about ab74044 citations in publications. We will update the on-line datasheet for this product as soon as we receive additional data. We however can guarantee that this product is specific to CLK1 protein. If the product fails to detect the target we will refund the money you pay. Full Abpromise guarantee is published on our website which can opened using following link; https://www.abcam.com/index.html?pageconfig=abpromise We apologize for any inconvenience this may cause.

Read More


Thank you for your email. I apologize for being late in getting back to you as our lab took more time to release this information than initially anticipated. They have let me know that the antibody is specific to CLK1 only. I hope this information will be helpful. Should you have any other question please do not hesitate to contact me.

Read More

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