Age-Related Differences in Plasma Proteins: How Plasma Proteins Change from Neonates to Adults

The incidence of major diseases such as cardiovascular disease, thrombosis and cancer increases with age and is the major cause of mortality world-wide, with neonates and children somehow protected from such diseases of ageing. We hypothesized that there are major developmental differences in plasma proteins and that these contribute to age-related changes in the incidence of major diseases. We evaluated the human plasma proteome in healthy neonates, children and adults using the 2D-DIGE approach. We demonstrate significant changes in number and abundance of up to 100 protein spots that have marked differences in during the transition of the plasma proteome from neonate and child through to adult. These proteins are known to be involved in numerous physiological processes such as iron transport and homeostasis, immune response, haemostasis and apoptosis, amongst others. Importantly, we determined that the proteins that are differentially expressed with age are not the same proteins that are differentially expressed with gender and that the degree of phosphorylation of plasma proteins also changes with age. Given the multi-functionality of these proteins in human physiology, understanding the differences in the plasma proteome in neonates and children compared to adults will make a major contribution to our understanding of developmental biology in humans.GE Healthcare Life Sciences Australia funded Sherif Tawfilis' time in the initial laboratory aspects of this project, some aspects of data analysis and preparation of the manuscript. This study was funded by internal Haematology Research Team funds. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

K0SK0S and K0SK± femtoscopy in pp collisions at √s = 5.02 and 13 TeV

Femtoscopic correlations with the particle pair combinations (KSKS0)-K-0 and (KSK +/-)-K-0 are studied in pp collisions at root s= 5.02 and 13 TeV by the ALICE experiment. At both energies, boson source parameters are extracted for both pair combinations, by fitting models based on Gaussian size distributions of the sources, to the measured two-particle correlation functions. The interaction model used for the (KSKS0)-K-0 analysis includes quantum statistics and strong final-state interactions through the f(0) (980) and a(0) (980) resonances. The model used for the (KSK +/-)-K-0 analysis includes only the final-state interaction through the a(0) resonance. Source parameters extracted in the present work are compared with published values from pp collisions at root s = 7 TeV and the different pair combinations are found to be consistent. From the observation that the strength of the (KSKS0)-K-0 correlations is significantly greater than the strength of the (KSK +/-)-K-0 correlations, the new results are compatible with the a(0) resonance being a tetraquark state of the form (q(1), (q(2)) over bar, s, (s) over bar), where q(1) and q(2) are uor d quarks. (C) 2022 European Organization for Nuclear Research, ALICE. Published by Elsevier B.V

Overlay of gel stained with Pro-Q Diamond Phosphoprotein Stain.

<p>Circled areas represent regions with differences in phosphorylation patterns between (A) Day 1 neonates and (B) adult samples. Red (Cy5) represents the total plasma proteome; Green (Cy3) represents the phosphoproteome.</p

Validation of the age-specific variation in alpha-2-macroglobulin.

<p>(A) western blot image; (B) semi-quantification of the western blot (densitometry units); (C) 2D-DIGE calculated relative log abundance.</p

Phosphorylated proteins.

<p>Results represent the spot volume ratio for total (Cy5) compared to phosphorylated (Cy3) protein. (-) Proteins that are not detectable in a particular age-group.</p

Effect of Na(+) binding on the conformation, stability and molecular recognition properties of thrombin

In the present work, the effect of Na(+) binding on the conformational, stability and molecular recognition properties of thrombin was investigated. The binding of Na(+) reduces the CD signal in the far-UV region, while increasing the intensity of the near-UV CD and fluorescence spectra. These spectroscopic changes have been assigned to perturbations in the environment of aromatic residues at the level of the S2 and S3 sites, as a result of global rigidification of the thrombin molecule. Indeed, the Na(+)-bound form is more stable to urea denaturation than the Na(+)-free form by ∼2 kcal/mol (1 cal≡4.184 J). Notably, the effects of cation binding on thrombin conformation and stability are specific to Na(+) and parallel the affinity order of univalent cations for the enzyme. The Na(+)-bound form is even more resistant to limited proteolysis by subtilisin, at the level of the 148-loop, which is suggestive of the more rigid conformation this segment assumes in the ‘fast’ form. Finally, we have used hirudin fragment 1–47 as a molecular probe of the conformation of thrombin recognition sites in the fast and ‘slow’ form. From the effects of amino acid substitutions on the affinity of fragment 1–47 for the enzyme allosteric forms, we concluded that the specificity sites of thrombin in the Na(+)-bound form are in a more open and permissible conformation, compared with the more closed structure they assume in the slow form. Taken together, our results indicate that the binding of Na(+) to thrombin serves to stabilize the enzyme into a more open and rigid conformation

Differentially expressed protein spots identified from the 2D-DIGE profiling of human plasma, with higher abundance in neonates and children compared to adults.

<p>Proteins were identified using MALTI-TOF/TOF. IPI – International Protein Index accession number. Protein spots 1–11 were identified from pH 3–11 gels; Protein spots 12–19 were identified from pH 4–7 gels. Protein score reflects the combined scores of all observed mass spectra that can be matched to amino acid sequences within a specific protein; higher score indicates a more confident match.</p