Microfibril structure masks fibrillin-2 in postnatal tissues.
نویسندگان
چکیده
Fibrillin microfibrils are polymeric structures present in connective tissues. The importance of fibrillin microfibrils to connective tissue function has been demonstrated by the multiple genetic disorders caused by mutations in fibrillins and in microfibril-associated molecules. However, knowledge of microfibril structure is limited, largely due to their insolubility. Most previous studies have focused on how fibrillin-1 is organized within microfibril polymers. In this study, an immunochemical approach was used to circumvent the insolubility of microfibrils to determine the role of fibrillin-2 in postnatal microfibril structure. Results obtained from studies of wild type and fibrillin-1 null tissues, using monoclonal and polyclonal antibodies with defined epitopes, demonstrated that N-terminal fibrillin-2 epitopes are masked in postnatal microfibrils and can be revealed by enzymatic digestion or by genetic ablation of Fbn1. From these studies, we conclude that fetal fibrillin polymers form an inner core within postnatal microfibrils and that microfibril structure evolves as growth and development proceed into the postnatal period. Furthermore, documentation of a novel cryptic site present in EGF4 in fibrillin-1 underscores the molecular complexity and tissue-specific differences in microfibril structure.
منابع مشابه
Fibrillins can co-assemble in fibrils, but fibrillin fibril composition displays cell-specific differences.
Fibrillins are microfibril-forming extracellular matrix macromolecules that modulate skeletal development. In humans, mutations in fibrillins result in long bone overgrowth as well as other distinct phenotypes. Whether fibrillins form independent microfibrillar networks or can co-polymerize, forming a single microfibril, is not known. However, this knowledge is required to determine whether phe...
متن کاملThe Journal of Biological Chemistry ADAMTSL6β rescues disorder in Marfan syndrome Saito et al, Page1 ADAMTSL6β rescues fibrillin-1 microfibril disorder in a Marfan syndrome mouse model through the promotion of fibrillin-1 assembly
Marfan’s syndrome (MFS) is a systemic disorder of the connective tissues caused by insufficient fibrillin-1 microfibril formation and can cause cardiac complications, emphysema, ocular lens dislocation and severe periodontal disease. A disintegrinlike metalloprotease domain with thrombospondin type I motifs like (ADAMTSL) 6β is a microfibril-associated extracellular matrix protein expressed in ...
متن کاملDifferential expression of fibrillin-3 adds to microfibril variety in human and avian, but not rodent, connective tissues.
The human genome contains three fibrillins: FBN1 and FBN2, both well characterized, and FBN3, reported only as a cDNA sequence. Like FBN2, the highest expression levels of FBN3 were found in fetal tissues, with only low levels in postnatal tissues. Immunolocalization demonstrated fibrillin-3 in extracellular microfibrils abundant in developing skeletal elements, skin, lung, kidney, and skeletal...
متن کاملBiogenesis of extracellular microfibrils: Multimerization of the fibrillin-1 C terminus into bead-like structures enables self-assembly.
Microfibrils are essential elements in elastic and nonelastic tissues contributing to homeostasis and growth factor regulation. Fibrillins form the core of these multicomponent assemblies. Various human genetic disorders, the fibrillinopathies, arise from mutations in fibrillins and are frequently associated with aberrant microfibril assembly. These disorders include Marfan syndrome, Weill-Marc...
متن کاملStructure of the Fibrillin-1 N-Terminal Domains Suggests that Heparan Sulfate Regulates the Early Stages of Microfibril Assembly
The human extracellular matrix glycoprotein fibrillin-1 is the primary component of the 10- to 12-nm-diameter microfibrils, which perform key structural and regulatory roles in connective tissues. Relatively little is known about the molecular mechanisms of fibrillin assembly into microfibrils. Studies using recombinant fibrillin fragments indicate that an interaction between the N- and C-termi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 285 26 شماره
صفحات -
تاریخ انتشار 2010