High impact information on MAGP2

• Further analysis of isolated microfibrils indicated that MAGP-2 was attached at two points along the microfibril substructure, "site 1" on the "beads" and "site 2" at the "shoulder" of the interbead region close to where the two "arms" fuse [1].
• Interestingly, no binding was detected to sequences near the N or C terminus where MAGP-1 and MAGP-2, respectively, were shown to interact with fibrillin-1 [2].
• Immunogold labeling of developing nuchal ligament tissue showed that MAGP-2 had regular covalent and periodic (about 56 nm) association with fibrillin-containing microfibrils of elastic fibers in this tissue [1].
• The locus of the human MAGP-2 gene was identified on chromosome 12 in the region of 12p12.3-12p13.1 [3].
• Elsewhere the MAGP-2 molecule is rich in serine and threonine residues and contains an RGD motif [3].

Biological context of MAGP2

• Expression screening of nuchal ligament cDNA libraries yielded a cDNA, cM10A (770 base pairs) which encodes amino acid sequences matching those of the MP25 peptides [3].
• In nuchal ligament, MAGP-2 mRNA expression appeared to peak around 180 days of fetal development, which correlates with the period of onset of elastinogenesis in this tissue [4].

Anatomical context of MAGP2

• Peptide sequences from MP25 proved to be unique, and affinity-purified anti-MP25 antibodies were shown, by immunofluorescence and immunoelectron microscopy, to localize specifically to the elastin-associated microfibrils [3].
• Further characterization of proteins associated with elastic fiber microfibrils including the molecular cloning of MAGP-2 (MP25) [3].
• MAGP-2 expression appeared to be higher in nuchal ligament, heart, and skeletal muscle and lower in aorta and kidney [4].
• In contrast to MAGP-1, MAGP-2 was not detected in the medial layer of fetal thoracic aorta and in much of the peritubular matrix of fetal and mature kidney and in the mature ocular zonule [4].
• Immunoelectron microscopy confirmed that MAGP-2 was specifically associated with fibrillin-containing microfibrils in nuchal ligament, dermis, adventitia of aorta, glomerular mesangium and perimysium [4].

Analytical, diagnostic and therapeutic context of MAGP2

• Northern blotting of RNA from tissues of a 210-day-old fetus indicated that steady-state MAGP-2 mRNA levels were highest in nuchal ligament [4].
• We developed an affinity-purified anti-MAGP-2 peptide antibody that specifically identified MAGP-2 on Western blots of purified matrix proteins and extracts of nuchal ligament [4].

References