The leucine-rich repeat protein PRELP binds perlecan and collagens and may function as a basement membrane anchor
The leucine-rich repeat protein PRELP binds perlecan and collagens and may function as a basement membrane anchor
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DOI：
10.1074/jbc.m108285200
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发表时间：
2002-04-26
影响因子：
4.8
通讯作者：
Aspberg, A
中科院分区：
文献类型：
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作者：
Bengtsson, E;Mörgelin, M;Aspberg, A
PRELP （proline arginine-rich end leucine-rich repeat protein）是结缔组织细胞外基质中与肝素结合的富亮氨酸重复序列蛋白。为了寻找该分子的天然配体和生物学功能，我们发现PRELP与基膜硫酸肝素蛋白聚糖结合。此外，携带硫酸肝素的重组perlecan结构域I和V与PRELP结合，而其他没有糖胺聚糖取代的结构域则不与PRELP结合。肝素，而不是硫酸软骨素，抑制了相互作用。无糖胺聚糖重组perlecan结构域V和突变结构域I不结合PRELP。表面等离子体共振测定了PRELP-perlecan相互作用的解离常数在3 ~ 18 nm范围内。正如预期的那样，没有肝素结合结构域的截断的PRELP没有与perlecan结合。共聚焦免疫组织化学显示，PRELP勾勒出基底膜，其位置与胰腺相邻。我们还发现PRELP通过其富含亮氨酸的重复结构域结合I型和11型胶原。电子显微镜观察到PRELP复合物同时与前胶原I的三螺旋区和perlecan的硫酸肝素链结合。基于PRELP的位置及其与perlecan硫酸肝素链和胶原的相互作用，我们提出了PRELP作为一种分子将基底膜锚定到底层结缔组织的功能。
PRELP (proline arginine-rich end leucine-rich repeat protein) is a heparin-binding leucine-rich repeat protein in connective tissue extracellular matrix. In search of natural ligands and biological functions of this molecule, we found that PRELP binds the basement membrane heparan sulfate proteoglycan perlecan. Also, recombinant perlecan domains I and V carrying heparan sulfate bound PRELP, whereas other domains without glycosaminoglycan substitution did not. Heparin, but not chondroitin sulfate, inhibited the interactions. Glycosaminoglycan-free recombinant perlecan domain V and mutated domain I did not bind PRELP. The dissociation constants of the PRELP-perlecan interactions were in the range of 3-18 nm as determined by surface plasmon resonance. As expected, truncated PRELP, without the heparin-binding domain, did not bind perlecan. Confocal immunohistochemistry showed that PRELP outlines basement membranes with a location adjacent to perlecan. We also found that PRELP binds collagen type I and type 11 through its leucine-rich repeat domain. Electron microscopy visualized a complex with PRELP binding simultaneously to the triple helical region of procollagen I and the heparan sulfate chains of perlecan. Based on the location of PRELP and its interaction with perlecan heparan sulfate chains and collagen, we propose a function of PRELP as a molecule anchoring basement membranes to the underlying connective tissue.