CUL4A / Cullin-4A · Western blot design guide

Design a Western Blot for CUL4A

Real validated CUL4A Western blot protocols, expected-band and isoform facts, troubleshooting for weak or shifted signal, and recommended anti-CUL4A WB antibodies. Everything you need to plan the experiment before you commit precious samples.

Evidence assembled September 2026 · For research use; verify linked source records and product datasheet before use

Western blot protocol sheet for CUL4A: expected band ~87.7 kDa, hero antibody A01579-1, catalog values and labelled standard workflow; separate PMC comparisons on the guide — Printable **CUL4A** Western blot protocol sheet — expected band ~87.7 kDa, antibody A01579-1, controls and PMC citations. Open the full CUL4A WB guide →

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CUL4A Western Blot Experimental Design Guide

Expected bands, validated protocols, controls and antibodies — the at-a-glance facts below, then the full design guide.

Must know before running

	Expected band	~87.7 kDa
	Observed band	~88 kDa
	Gel	5–20% (catalog A01579-1)
	Negative control ⓘ	Suggested KO / knockdown lysate

Important caveats

Reasons your observed band may differ from the expected size.

	PTM	Phosphorylated + Ubl conjugation
	Caveat	Modification-state controls
	Gene-set association	MSigDB Hallmark membership
	Isoform	2 isoform(s)

Section 1

Real Curated CUL4A Western Blot Protocols

The A01579-1 protocol combines labelled catalog values with standard starting conditions. Published comparisons retain their own sample, reagent and detection scope.

Recommended Western blot protocol parameters
Sample / lysate	human Hela, human COLO-320, human MDA-MB-231 (catalog A01579-1)
Gel %	5–20% (catalog A01579-1)
Load	50ug; reducing conditions (catalog A01579-1)
Transfer	a Nitrocellulose membrane at 150mA for 50-90 minutes (catalog A01579-1)
Membrane	Nitrocellulose membrane (catalog A01579-1)
Blocking	5% Non-fat Milk/ TBS for 1.5 hour at RT (catalog A01579-1)
Primary antibody	A01579-1 · 0.5 μg/mL (catalog A01579-1)
Primary incubation	overnight at 4°C (catalog A01579-1)
Secondary antibody	goat anti-rabbit IgG-HRP, 1:10000 (catalog A01579-1)
Secondary incubation	1.5 hour at RT (catalog A01579-1)
Wash	TBS-0.1%Tween 3 times with 5 minutes each (catalog A01579-1)
Detection	ECL (catalog A01579-1)

Section 2

What Is the Expected CUL4A Western Blot Band Size?

CUL4A is predicted at 87.7 kDa and observed at ~88 kDa; its isoforms and self-association do not establish additional migrating bands.

What am I looking at on my blot?
Band at ~88 kDa	Matches the empirical CUL4A band and its 87.7 kDa predicted mass
Additional band at a different mass	Could reflect isoforms 1 and 2; their migration difference is unknown
Single band without an isoform doublet	Isoforms 1 and 2 need not resolve as separate bands
Higher band	Could reflect CUL4A self-association if it survives electrophoresis; band identity requires confirmation

💡Expected CUL4A appearanceCUL4A has a predicted mass of 87.7 kDa and an empirical band at ~88 kDa; confirm band identity with an antibody control or CUL4A depletion.

How each factor affects band size
UniProt predicted mass	Places full-length CUL4A near 87.7 kDa, consistent with the observed ~88 kDa band
Isoform 1	Its individual mass and migration relative to isoform 2 are not supplied
Isoform 2	Its individual mass and migration relative to isoform 1 are not supplied
CUL4A self-association	Could yield a higher species if association survives electrophoresis; no such band is established

Why is my band missing or off?
Situation	Likely cause	Next action
Band higher than expected	CUL4A self-association is possible, but persistence during electrophoresis is unproven	Compare reducing and denaturing conditions and confirm identity by CUL4A depletion
Band lower than expected	Isoform variation is possible, but isoform sizes are unknown	Check isoform coverage of the antibody and confirm the band by CUL4A depletion
Multiple bands	Isoforms 1 and 2 may contribute, but distinct migration is unproven	Use isoform-specific controls and CUL4A depletion to identify bands
Weak or no signal	CUL4A may be below the assay's detection limit in the sample	Include a positive lysate and verify loading and antibody performance
Fragments below expected size	Sample degradation may produce fragments	Prepare fresh lysate with protease inhibitors and confirm bands by CUL4A depletion

Source: UniProt Q13619 Human Protein Atlas product datasheet (A01579-1)

Experiment evidence

Western blot images showing CUL4A band

A01579-1 · CUL4A

M01579 · CUL4A

← swipe / scroll for more images →

Real WB data behind the band-size expectations in this section.

Sample controls for CUL4A Western blot

🧪For positive controls for CUL4A in Western blot, you can use an HPA-IHC candidate positive sample once one is identified.

Positive control: No high/medium HPA tissue identified

Negative control: Suggested KO / knockdown lysate

Loading controls: Run GAPDH, β-actin, and a total-protein stain alongside the samples.

⚠️Feasibility: HPA data are unavailable, so tissue controls cannot be validated; use a knockdown or KO line for a negative control.

HPA tissue expression evidence for CUL4A

Comprehensive Human Protein Atlas IHC scoring per tissue. Rows are taken directly from the HPA tissue chart — click any row's HPA link to view the source.

Higher expression tissues · candidate positive controls from IHC

Tissue	Cell type	Level	Evidence	Source
No high/medium HPA tissues identified in the supplied evidence.

Lower expression tissues · IHC evidence, not confirmed WB-negative controls

Tissue	Cell type	Level	Evidence	Source
No lower-expression tissue rows available in the supplied evidence.

Section 3

Advanced CUL4A Western Blot Tips

Deeper troubleshooting and optimisation questions for CUL4A, answered from its protein features.

How should CUL4A band migration be interpreted?

Band shift · Use the separately labelled calculated mass and catalog-observed evidence above. A sequence annotation does not establish an observed migration shift. Verify target identity with orthogonal controls.

Could CUL4A isoforms produce different bands?

Isoforms · UniProt lists isoforms 1 and 2. Isoform 2 lacks residues 1–100 of the canonical sequence, so it has a shorter sequence; its apparent migration is not supplied. Check which isoform your antibody recognizes before assigning a second band.

Does phosphorylation explain a CUL4A band shift?

PTM · UniProt lists phosphoserine at position 10 in the canonical sequence. That residue falls within the segment missing from isoform 2. Feature presence alone does not establish a visible shift; use a phosphatase comparison if testing whether phosphorylation affects your bands. Check the numbering convention before comparing this site with antibody documentation.

Does this guide establish induction of CUL4A?

Induction · No general induction response is established by this guide. A pathway or gene-set association is not evidence of induction in a particular specimen. Verify the relevant treatment and control in a target-specific experiment.

How should transfer be checked for CUL4A?

Transfer · Standard workflow guidance: verify transfer efficiency for the intended target size before interpreting a weak signal. Use total-protein assessment and optimize transfer for the membrane, gel and apparatus; the labelled catalog values take precedence.

How should blocking be optimized?

Blocking · Standard workflow guidance: follow the A01579-1 datasheet where specified. Otherwise compare 5% milk or 5% BSA in TBST; for a phospho-specific assay start with BSA. Optimize background and specific signal with matched controls.

How should CUL4A bands be quantified across samples?

Quantitation · Use the same band assignment across samples and state whether you quantify one band or sum bands attributed to CUL4A. The two listed isoforms can differ in antibody recognition because isoform 2 lacks residues 1–100; verify the epitope before comparing isoform signals.

Why is the CUL4A band near 88 kDa?

Interpretation · The observed band near 88 kDa closely matches the predicted 87.7 kDa mass of canonical CUL4A. The listed features do not establish a modification-related shift.

Isoform 2 lacks canonical residues 1–100. An antibody targeting that segment may detect isoform 1 without detecting isoform 2. Check the antibody's mapped epitope before treating an absent lower band as evidence that isoform 2 is absent.

Consider the listed isoform 2, which lacks canonical residues 1–100, and check whether the antibody can recognize it. CUL4A can self-associate and participates in protein complexes, but those features alone do not identify a particular Western-blot band. The listed phosphoserine at canonical position 10 also does not establish a visible shift.

Boster reagents

CUL4A Western Blot Antibodies

Catalog antibodies with Western blot application and product-specific WB images. Evaluate suitability with the reported sample, controls and experimental conditions.

Real WB data

Western blot analysis of Cullin 4a using anti-Cullin 4a antibody (A01579-1). Electrophoresis was performed on a 5-20% SDS-PAGE gel at 70V (Stacking gel) / 90V (Resolving gel) for 2-3 hours. The sample well of each lane was loaded with 50ug of sample under reducing conditions. Lane 1: human Hela whole cell lysates, Lane 2: human COLO-320 whole cell lysates, Lane 3: human MDA-MB-231 whole cell lysates, Lane 4: human Jurkat whole cell lysates, Lane 5: human PANC-1 whole cell lysates. After Electrophoresis, proteins were transferred to a Nitrocellulose membrane at 150mA for 50-90 minutes. Blocked the membrane with 5% Non-fat Milk/ TBS for 1.5 hour at RT. The membrane was incubated with rabbit anti-Cullin 4a antigen affinity purified polyclonal antibody (Catalog # A01579-1) at 0.5 μg/mL overnight at 4°C, then washed with TBS-0.1%Tween 3 times with 5 minutes each and probed with a goat anti-rabbit IgG-HRP secondary antibody at a dilution of 1:10000 for 1.5 hour at RT. The signal is developed using an Enhanced Chemiluminescent detection (ECL) kit (Catalog # EK1002) with Tanon 5200 system. A specific band was detected for Cullin 4a at approximately 88KD. The expected band size for Cullin 4a is at 88KD.

Anti-Cullin 4a/CUL4A Antibody Picoband®

Cat # A01579-1

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Real WB data

Western blot analysis of Cullin4A using anti-Cullin4A antibody (M01579). Electrophoresis was performed on a 5-20% SDS-PAGE gel at 70V (Stacking gel) / 90V (Resolving gel) for 2-3 hours. The sample well of each lane was loaded with 30 ug of sample under reducing conditions. Lane 1: human Hela whole cell lysates. After electrophoresis, proteins were transferred to a nitrocellulose membrane at 150 mA for 50-90 minutes. Blocked the membrane with 5% non-fat milk/TBS for 1.5 hour at RT. The membrane was incubated with rabbit anti-Cullin4A antigen affinity purified monoclonal antibody (Catalog # M01579) at 1:1000 overnight at 4°C, then washed with TBS-0.1%Tween 3 times with 5 minutes each and probed with a goat anti-rabbit IgG-HRP secondary antibody at a dilution of 1:500 for 1.5 hour at RT. The signal is developed using an Enhanced Chemiluminescent detection (ECL) kit (Catalog # EK1002) with Tanon 5200 system. A specific band was detected for Cullin4A at approximately 88 kDa. The expected band size for Cullin4A is at 88 kDa.

Anti-Cullin4A Monoclonal Antibody

Cat # M01579

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Both listed anti-CUL4A antibodies have Western blot images showing an approximately 88 kDa band in human cell lysates. The supplied captions describe these blot results; they do not provide independent specificity validation or mouse or rat blot examples.

Which to pick: Choose A01579-1 for listed human, mouse, or rat reactivity and a blot shown across five human cell lines. Choose human-reactive M01579 if you prefer a monoclonal antibody; its blot shows HeLa lysate. Both images show an approximately 88 kDa band.

Source: BosterBio CUL4A gene-info card — filtered to Western-blot-capable antibodies; each card shows that product's actual WB validation figure.

References

UniProt Consortium. UniProt entry Q13619.
Human Protein Atlas. CUL4A tissue expression.
PMC6501127 — target-verified WB comparison
PMC5593474 — target-verified WB comparison
PMC5385398 — target-verified WB comparison