2 research outputs found
HILAQ: A Novel Strategy for Newly Synthesized Protein Quantification
Here
we describe a new strategy, HILAQ (Heavy Isotope Labeled Azidohomoalanine
Quantification), to rapidly quantify the molecular vulnerability profile
to oxytosis, which is an oxidative stress-induced programed cell death
pathway that has been reported to be involved in aging and neurodegenerative
diseases. HILAQ was able to quantify 1962 newly synthesized proteins
(NSPs) after 1 h of pulse labeling in HEK293T cell line, while 353
proteins were quantified using the previously published QuaNCAT protocol.
HILAQ was successfully applied to the HT22 oxytosis model. 226 proteins
were found to have a two-fold change in abundance, and 108 proteins
were enriched in the cell death pathway, demonstrating the utility
of HT22 cells as a tool to study the molecular details of cell death
involved in neurodegenerative diseases. The HILAQ strategy simplifies
the analysis of newly synthesized proteomes through the use of isobaric
labels and achieves higher sensitivity than previously published methods
Pulsed Azidohomoalanine Labeling in Mammals (PALM) Detects Changes in Liver-Specific LKB1 Knockout Mice
Quantification
of proteomes by mass spectrometry has proven to
be useful to study human pathology recapitulated in cellular or animal
models of disease. Enriching and quantifying newly synthesized proteins
(NSPs) at set time points by mass spectrometry has the potential to
identify important early regulatory or expression changes associated
with disease states or perturbations. NSP can be enriched from proteomes
by employing pulsed introduction of the noncanonical amino acid, azidohomoalanine
(AHA). We demonstrate that pulsed introduction of AHA in the feed
of mice can label and identify NSP from multiple tissues. Furthermore,
we quantitate differences in new protein expression resulting from
CRE-LOX initiated knockout of LKB1 in mouse livers. Overall, the PALM
strategy allows for the first time in vivo labeling of mouse tissues
to differentiate protein synthesis rates at discrete time points