PMC

Flow of experimental methods for the ¹⁴N/¹⁵N serum samples. After combining the blood samples in equal amounts and forming serum, all mouse samples were prepared and analyzed using the general methods described.

Mouse metabolic labeling schema. Eight mice were fed diets of >98% ¹⁵N or natural abundance ¹⁴N Spirulina starting at 20 days of age. Blood was collected at 40, 52, and 66 days of age from each mouse and combined in equal amounts to form four ¹⁴N/¹⁵N samples. Reciprocal metabolic labels were used in each litter to make two reciprocally labeled samples that controlled for isotopic effects.

String-db version 9.0 (www.string-db.org) interacting protein web for the relationships between differential expression proteins listed in and . This web was generated with human versions of the proteins and used a medium confidence of 0.400 or higher. Colored lines represent the type of interaction between the two proteins. Yellow-green: associated proteins are co-mentioned in PubMed abstracts, cyan: proteins are associated in curated databases, purple-pink: experimental connections, black lines: co-expressed proteins, and light blue: sequence homology. Asterisks and diamonds highlight common Gene Ontology Annotations for these proteins.

Downregulated proteins in the ¹⁴N/¹⁵N Min mouse displaying high statistical confidence at 52 and/or 66 days in at least three out of four mouse samples. Solid bars on the bar chart represent the geometric mean of the log2 area ratios (all ratios are shown as Min/WT) that are statistically significant. Significance was defined as a U-value less than 0.05 and corresponding q-values less than 0.05. Hashed bars represent area ratios that do not pass statistical cutoffs for significance. Outlined bars with light dots represent values where there is no statistical data due to the presence of only one data point.

Statistically significant changes in protein expression as determined by relative quantification of SRM-MS data using stable isotope labeled peptides. Maltase-glucoamylase (MGAM), collagen 1 alpha-1(I) chain (COL1A1), inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3) and coagulation factor V (F5) all matched the ¹⁴N/¹⁵N quantitative data. Epidermal growth factor receptor (EGFR) showed opposite expression compared to the ¹⁴N/¹⁵N quantitative data. The other proteins quantified either showed no statistical change or were not quantified due to too low of an abundant endogenous peptide peak. Error bars represent the average standard error of the technical replicates from all biological samples.

Upregulated proteins in the ¹⁴N/¹⁵N Min mouse displaying high statistical confidence at 52 and/or 66 days in at least three out of four mouse samples. Solid bars on the bar chart represent the geometric mean of the log2 area ratios (all ratios are shown as Min/WT) that are statistically significant. Significance was defined as a U-value less than 0.05 and corresponding q-values less than 0.05. Hashed bars represent area ratios that do not pass statistical cutoffs for significance. Outlined bars with light dots represent values where there is no statistical data due to the presence of only one data point.
^aMASCOT database searches for the reciprocal ¹⁵N labeled proteins show substantial increases in this protein in sample 4 at 52 days although this data is not represented in this graph (all values shown in the figure are from ¹⁴N MASCOT searches).