Further functional assays pertaining to MAGP-1, such as gene knock-down studies in skin cells and tissues, should be carried out to better elucidate how this type of age-related change affects the total elastic network.
The first immunolabeling was performed by overnight incubation at 4°C with a polyclonal antibody to MAGP-1 (MFAP-2; Sigma-Aldrich, Milan, Italy) diluted 1 25 in PBS containing 0.5% BSA followed by incubation for 1 h with a goat anti-rabbit Alexa Fluor 594-conjugated immunoglobulin G (IgG) antibody (1 1,000 dilution in PBS with 1% BSA; Invitrogen, Milan, Italy).
A mature mycolic acid is eventually transferred either to arabinogalactan (to form mAGP) in part by the Ag85 proteins, or to an α,α-trehalose-6-phosphate (T6P, leading to TMM) by an unknown mycolyltransferase [9].
We then examined each MAGP to see if the two genes were functionally coupled (see details in Additional file 6).
We used the 1064 MAGP to investigate the nature of the "stabilization" forces that might maintain the clusters' integrity.
Overall, these findings suggest that Tsk fibrillin alters the binding of fibrillin to other matrix proteins and that this altered binding appears to stimulate increased MAGP-2 and fibulin-2 matrix.
To find out those MAGP not maintained by operon structures, we examined the genes from each MAGP in all the bacterial chromosomes.
When putting aside the operon effect, if this new MA showed that the two genes still had a very strong attraction (3 sigma larger than the mean of MA drawn from pairs of genes randomly distributed; the mean and standard deviation were from the large class following a normal distribution, retrieved from Figure 7, see Results), we then concluded that this MAGP was not due to operons.
This showed that 618 (58%) MAGP were composed of genes belonging to the same functional category, among which 391 were MAGP maintained by operons.
Long-term photoaging appears to result in the progression of MAGP-1 loss in the follicular regions and in the reticular dermis, which may lead to fragility and instability of the dermal matrix, and contribute to the various signs of an aged appearance such as wrinkles, sagging, loss of elasticity and bounciness, and enlarged pores.
PI, Persistence Index MA, Mutual Attractivity MAGP, Mutually Attracted Gene Pairs All authors contributed to the writing of the manuscript.
