Design a Western Blot for HTRA2

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.

Isoforms · Yes. Four isoforms are listed. Relative to the canonical sequence, isoform 2 lacks residues 238..302 and 372..403; isoform 3 changes residue 313 and lacks 372..403; isoform 4 replaces residues 314..458. These are UniProt coordinates. Check whether the antibody's epitope is retained before assigning a band to an isoform.

PTM · The supplied features list no modified residue or glycosylation site, although the keywords include Ubl conjugation. They do not identify a modification that explains a particular band shift. Check processing and the listed isoform sequences before attributing an unexpected band to modification.

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.

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.

Blocking · Standard workflow guidance: follow the A01941-3 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.

Quantitation · Keep sample fraction and band assignment consistent across lanes. HTRA2 occurs predominantly in the mitochondrial intermembrane space, can move to the cytosol after apoptotic stimuli, and has four listed isoforms. Quantifying a single band without resolving these possibilities may mix changes in abundance with changes in localization or isoform detection.

Interpretation · 48.8 kDa is the predicted mass of the full-length protein. UniProt lists a propeptide at residues 32..133, so processing could contribute to a smaller band. The supplied observations place a band near 36 kDa, but the feature alone does not establish that band's identity or exact cleavage site.

The canonical sequence is 458 residues, and UniProt marks residues 32..133 as a propeptide. Compare bands with the predicted full-length mass of 48.8 kDa and the observed band near 36 kDa, while treating either assignment as provisional until validated experimentally.

HTRA2 is predominantly in the mitochondrial intermembrane space and can be released into the cytosol after apoptotic stimuli such as UV treatment. When comparing conditions, measure the same fraction each time; a change in cytosolic signal may reflect redistribution rather than a change in total HTRA2.

Consider the listed propeptide at UniProt residues 32..133, autocatalytic cleavage keyword, and isoform sequence changes when evaluating additional bands. None alone identifies a band. Confirm an assignment with an antibody whose epitope is present in the proposed sequence and compare the expected sample fractions.