Structural determinant of the vesicle aggregation activity of annexin I.
نویسندگان
چکیده
Some annexins, including annexins I, II, IV, and VII, can promote membrane aggregation. To identify amino acids involved in annexin I-mediated membrane aggregation, we generated truncated mutants of human annexin I lacking various parts of the amino terminus. The in vitro vesicle binding and aggregation activities of these mutants indicated that both the amino-terminal region of annexin I spanning residues 26-29 and the carboxy-terminal core are involved in membrane aggregation. This notion was further supported by the finding that a chimera composed of residues 24-35 of annexin I and the core of annexin V has vesicle aggregation activity that is significantly higher than that of annexin V but lower than that of annexin I. Further site-specific mutations in the amino-terminal region of annexin I indicated that Lys-26 and Lys-29 are essential for its membrane aggregation activity. The comparison of tryptic digest patterns of free and vesicle-bound wild type and K29E mutant suggests that a primary role of Lys-26 and Lys-29 is to induce and stabilize an active conformation of annexin I for vesicle aggregation.
منابع مشابه
Roles of individual domains of annexin I in its vesicle binding and vesicle aggregation: a comprehensive mutagenesis study.
To understand the mechanism by which annexin I induces membrane aggregation, a comprehensive mutagenesis of all six Ca2+-binding sites was performed. When the cap residues of type II Ca2+-binding sites were systematically mutated to Ala, a type II site in domain II was shown to be essential for Ca2+-dependent vesicle binding of annexin I. Domain II was not, however, directly involved in vesicle...
متن کاملThe Effect of Hoffmeister Salts on the Chaperoning Action of β-Casein in Preventing Aggregation of Reduced β-Lactalbumin
Protein aggregation and precipitation is associated with many debilitating diseases including Alzheimer's, Parkinson's, and light-chain amyloidosis. β-Casein, a member of the casein family, has been demonstrated to exhibit chaperone-like activity to protect protein form aggregation. Hofmeister salts (lyotropice series) are a class of ions which have an effect on the solubility and also the stab...
متن کاملMechanism of annexin I-mediated membrane aggregation.
It has been proposed that annexin I has two separate interaction sites that are involved in membrane binding and aggregation, respectively. To better understand the mechanism of annexin I-mediated membrane aggregation, we investigated the properties of the inducible secondary interaction site implicated in membrane aggregation. X-ray specular reflectivity measurements showed that the thickness ...
متن کاملMembrane-induced folding and structure of membrane-bound annexin A1 N-terminal peptides: implications for annexin-induced membrane aggregation.
Annexins constitute a family of calcium-dependent membrane-binding proteins and can be classified into two groups, depending on the length of the N-terminal domain unique for each individual annexin. The N-terminal domain of annexin A1 can adopt an alpha-helical conformation and has been implicated in mediating the membrane aggregation behavior of this protein. Although the calcium-independent ...
متن کاملO-10: A Marked Animal-Vegetal Polarity in The Localization of Na+,K+-ATPase Activity and Its Down-Regulation Following Progesterone-Induced Maturation
Background: Polarized cells are key to the process of differentiation. Xenopus oocyte is a polarized cell that has complete blue-print to differentiate 3 germ layers following fertilization, as key determinant molecules (Proteins and RNAs) are asymmetrically localized. The objective of this work was to localize Na+, K+-ATPase activity along animal-vegetal axis of polarized Xenopus oocyte and fo...
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:
- Biochemistry
دوره 38 42 شماره
صفحات -
تاریخ انتشار 1999