Iodination of mature cathepsin D in thyrocytes as an indicator for its transport to the cell surface

doi:10.1016/S0171-9335(98)80017-4

European Journal of Cell Biology

Volume 76, Issue 1, May 1998, Pages 53-62

https://doi.org/10.1016/S0171-9335(98)80017-4 Get rights and content

Abstract

Thyrocytes are known for their ability to iodinate thyroglobulin from which the thyroid hormones are generated. In the intact thyroid gland the iodination process is almost exclusively executed at the apical plasma membrane of thyroid epithelial cells. Here, we show that freshly isolated thyrocytes iodinated polypeptides other than thyroglobulin and that one of the major iodinated polypeptides was the mature form of the lysosomal protease cathepsin D (CD). The detection of mature CD as an iodinated polypeptide suggested that a fraction of the lysosomally maturated enzyme was delivered to the apical plasma membrane where it became available for iodination. After labeling of thyrocytes with [³⁵S]methionine/cysteine overnight part of the mature CD was released into the culture medium. This was abolished by inhibiting maturation of CD with NH₄Cl, indicating that mature CD appeared in the medium after its proteolytic maturation in an acidic compartment. Besides CD other soluble lysosomal polypeptides like the β-N-acetylhexosaminidase and the sphingolipid-activating protein D (Sap D) were iodinated and partially secreted as mature polypeptides. In contrast, the membrane-associated lysosomal ceramidase was iodinated and partially secreted as immature single-chain enzyme and not as fully maturated two-chain enzyme. These data indicate that a portion of mature CD and other soluble lysosomal enzymes is delivered from lysosomes to the cell surface whereas some membrane-associated enzymes from the terminal lysosomel compartment are efficiently excluded from this process.

References (55)

S. Diment et al.
Cathepsin D is membrane-associated in macrophage endosomes
J. Biol. Chem
(1988)
A.D. Dunn et al.
Thyroglobulin processing by thyroidal proteases
Major sites of cleavage by cathepsins B, D and L. J. Biol. Chem
(1991)
A.H. Erickson et al.
Biosynthesis of a lysosomal enzyme
J. Biol. Chem
(1981)
W. Fürst et al.
Activator proteins and topology of lysosomal sphingolipid catabolism
Biochim. Biophys. Acta
(1992)
V. Gieselmann et al.
Processing of human cathepsin D in lysosomes in vitro
J. Biol. Chem
(1985)
G.M. Griffiths
Secretory lysosomes - a special mechanism of regulated secretion in haemopoietic cells
Trends Cell Biol
(1996)
F.G. Guarnieri et al.
The motif Tyr-X-X-hydrophobic residue mediates lysosomal membrane targeting of lysosome-associated membrane protein 1
J. Biol. Chem
(1993)
A. Hasilik et al.
Biosynthesis of lysosomal enzymes in fibroblasts
J. Biol. Chem
(1980)
R. Kuliawat et al.
Intracellular iodination of thyroglobulin in filter-polarized thyrocytes leads to the synthesis and basolateral secretion of thyroid hormone
J. Biol. Chem
(1994)
R. Kuliawat et al.
Polarized distribution and delivery of plasma membrane proteins in thyroid follicular epithelial cells
J. Biol. Chem
(1995)

J. Lippincott-Schwartz et al.

Cycling of the integral membrane glycoprotein, LEP100, between plasma membrane and lysosomes: kinetic and morphological analysis

Cell

(1987)

D.J. Mahuran et al.

Proteolytic processing of pro-α and pro-β precursors from human β-hexosaminidase

J. Biol. Chem.

(1988)

G.R. Richo et al.

Structural requirements of procathepsin D activation and maturation

J. Biol. Chem

(1994)

B. Rousset et al.

Thyroid hormone residues are released from thyroglobulin with only limited alteration of the thyroglobulin structure

J. Biol. Chem

(1989)

R. Seljelid

Endocytosis in thyroid follicle cells

V On the redistribution of cytosomes following stimulation with thyrotropic hormone. J. Ultrastruct. Res

(1967)

K. Akasaki et al.

Cycling of two endogenous lysosomal membrane proteins, lamp-2 and acid phosphatase, between the cell surface and lysosomes in cultured rat hepatocytes

J. Biochem. (Tokio)

(1993)

U. Berndorfer et al.

Multimerization of thyroglobulin (TG) during extracellular storage: Isolation of highly cross-linked TG from human thyroids

J. Clin. Endocrinol. Metab

(1996)

M. Braun et al.

Lysosomal acid phosphatase is transported to lysosomes via the cell surface

EMBO J

(1989)

K. Brix et al.

Extrathyroidal release of thyroid hormones from thyroglobulin by J774 mouse macrophages

J. Clin. Invest

(1994)

K. Brix et al.

Evidence for extracellularly acting cathepsins mediating thyroid hormone liberation in thyroid epithelial cells

Endocrinology

(1996)

M.R. Buck et al.

Degradation of extracellular-matrix proteins by human cathepsin B from normal and tumor tissues

Biochem. J

(1992)

M. Cantz et al.

Corrective factors for inborn errors of mucopolysaccharide metabolism

Methods Enzymol

(1972)

R. Delbrück et al.

Proteolytic processing of cathepsin D in prelysosomel organelles

Eur. J. Cell Biol

(1994)

O. Diettrich et al.

Purification of lysosomal membrane proteins from human placenta

Eur. J. Cell Biol

(1996)

B. Dubois et al.

Thyroglobulin (Tg) hydrolysis starts in prelysosomes

A.D. Dunn et al.

Cysteine proteinases from human thyroids and their action on thyroglobulin

Endocrinology

(1988)

R. Ekholm et al.

Site of iodination in the rat thyroid gland deduced from electron microscopic autoradiographs

Endocrinology

(1975)

Cited by (20)

Treatment of rat thyrocytes in vitro with cathepsin B and L inhibitors results in disruption of primary cilia leading to redistribution of the trace amine associated receptor 1 to the endoplasmic reticulum
2019, Biochimie
Citation Excerpt :
Hence, trafficking of cathepsins B and L in distinct and separate vesicles could be an underlying reason for the herein observed divergence in cathepsin B and L protein amounts secreted from FRT cells. Furthermore, the presence of binding sites specific for cathepsin L at the primary cilium of FRT cells could explain, in principle, the difference in sub-cellular localization between cathepsins B and L. However, the nature of cathepsin binding sites at the apical plasma membrane of thyrocytes adjacent to the thyroid follicle lumen is not yet fully understood, and investigations have so far only included the aspartic cathepsin D but less attention was paid to cysteine cathepsin binding to thyrocytes [7,17,45]. In other cellular systems, namely in colorectal carcinoma cells it was shown that secreted and proteolytically active cathepsin B re-associates with the plasma membrane in flask-like indentations, the caveoli [46,47].
Taar1 is a G protein-coupled receptor (GPCR) confined to primary cilia of rodent thyroid epithelial cells. Taar1-deficient mouse thyroid follicles feature luminal accumulation of thyroglobulin suggesting that Taar1 acts as a regulator of extra- and pericellular thyroglobulin processing, which is mediated by cysteine cathepsin proteases present at the apical plasma membrane of rodent thyrocytes.
Here, by immunostaining and confocal laser scanning microscopy, we demonstrated co-localization of cathepsin L, but only little cathepsin B, with Taar1 at primary cilia of rat thyrocytes, the FRT cells. Because proteases were shown to affect half-lives of certain receptors, we determined the effect of cathepsin activity inhibition on sub-cellular localization of Taar1 in FRT cells, whereupon Taar1 localization altered such that it was retained in compartments of the secretory pathway. Since the same effect on Taar1 localization was observed in both cathepsin B and L inhibitor-treated cells, the interaction of cathepsin activities and sub-cellular localization of Taar1 was thought to be indirect. Indeed, we observed that cathepsin inhibition resulted in a lack of primary cilia from FRT cells. Next, we proved that primary cilia are a necessity for Taar1 trafficking to reach the plasma membrane of FRT cells, since the disruption of primary cilia by treatment with β-cyclodextrin resulted in Taar1 retention in compartments of the secretory pathway. Furthermore, in less well-polarized rat thyrocytes, namely in FRTL-5 cells lacking primary cilia, Taar1 was mainly confined to the compartments of the secretory pathway.
We conclude that Taar1 localization in polarized thyroid epithelial cells requires the presence of primary cilia, which is dependent on the proteolytic activity of cysteine cathepsins B and L.
Are there Side Effects when Using Supraphysiologic Levels of Iodine in Treatment Regimens?
2009, Comprehensive Handbook of Iodine: Nutritional, Biochemical, Pathological and Therapeutic Aspects
This chapter examines the side-effects associated with chronic daily oral administration of molecular iodine (I₋) at levels above the recommended dietary tolerable upper intake level (UL), using controlled studies in mastalgia patients whose symptoms are associated with fibrocystic breast tissue. The recommended dietary allowance (RDA) for iodine in adult men and women in the United States is 150 μg/day; the dietary UL suggested for the general population is 1100 μg/day (1.1 mg/day). The thought process that underlies the RDA and UL incorporates safety considerations and adequacy of thyroid function. Iodide oxidation in tissues known to concentrate iodide (thyroid, mammary) yields at least two different iodine species that can iodinate biomolecules. The pharmacological and toxicological profiles of orally administered iodide and I− are distinct; iodide is more thyrotoxic than I₋. Daily I₋ treatment of women at doses up to 5½ times the UL is not associated with an increase in overt thyroid disease. Elevated rates of subclinical hypothyroidism are likely in iodine-naive women treated with I₋ at levels higher than the recommended UL. The incidence of subclinical thyroid conditions in iodine-adapted patients increases with dose above 3 mg/day of I₋. Two double blind, randomized, placebo-controlled studies indicate a beneficial effect of I₋ in patients with severe mastalgia dosed daily at levels that are at least three times above the UL.
Are there Side Effects when Using Supraphysiologic Levels of Iodine in Treatment Regimens?
2009, Comprehensive Handbook of Iodine
This chapter examines the side-effects associated with chronic daily oral administration of molecular iodine (I₋) at levels above the recommended dietary tolerable upper intake level (UL), using controlled studies in mastalgia patients whose symptoms are associated with fibrocystic breast tissue. The recommended dietary allowance (RDA) for iodine in adult men and women in the United States is 150 μg/day; the dietary UL suggested for the general population is 1100 μg/day (1.1 mg/day). The thought process that underlies the RDA and UL incorporates safety considerations and adequacy of thyroid function. Iodide oxidation in tissues known to concentrate iodide (thyroid, mammary) yields at least two different iodine species that can iodinate biomolecules. The pharmacological and toxicological profiles of orally administered iodide and I− are distinct; iodide is more thyrotoxic than I₋. Daily I₋ treatment of women at doses up to 5½ times the UL is not associated with an increase in overt thyroid disease. Elevated rates of subclinical hypothyroidism are likely in iodine-naive women treated with I₋ at levels higher than the recommended UL. The incidence of subclinical thyroid conditions in iodine-adapted patients increases with dose above 3 mg/day of I₋. Two double blind, randomized, placebo-controlled studies indicate a beneficial effect of I₋ in patients with severe mastalgia dosed daily at levels that are at least three times above the UL.
Autoproteolytic cleavage and activation of human acid ceramidase
2008, Journal of Biological Chemistry
Herein we report the mechanism of human acid ceramidase (AC; N-acylsphingosine deacylase) cleavage and activation. A highly purified, recombinant human AC precursor underwent self-cleavage into α and β subunits, similar to other members of the N-terminal nucleophile hydrolase superfamily. This reaction proceeded with first order kinetics, characteristic of self-cleavage. AC self-cleavage occurred most rapidly at acidic pH, but also at neutral pH. Site-directed mutagenesis and expression studies demonstrated that Cys-143 was an essential nucleophile that was required at the cleavage site. Other amino acids participating in AC cleavage included Arg-159 and Asp-162. Mutations at these three amino acids prevented AC cleavage and activity, the latter assessed using BODIPY-conjugated ceramide. We propose the following mechanism for AC self-cleavage and activation. Asp-162 likely forms a hydrogen bond with Cys-143, initiating a conformational change that allows Arg-159 to act as a proton acceptor. This, in turn, facilitates an intermediate thioether bond between Cys-143 and Ile-142, the site of AC cleavage. Hydrolysis of this bond is catalyzed by water. Treatment of recombinant AC with the cysteine protease inhibitor, methyl methanethiosulfonate, inhibited both cleavage and enzymatic activity, further indicating that cysteine-mediated self-cleavage is required for ceramide hydrolysis.
Identification of plasma membrane associated mature β-hexosaminidase A, active towards GM2 ganglioside, in human fibroblasts
2005, FEBS Letters
Mature β-hexosaminidase A has been found associated to the external leaflet of plasma membrane of cultured fibroblasts. The plasma membrane association of β-hexosaminidase A has been directly determined by cell surface biotinylation followed by affinity chromatography purification of the biotinylated proteins, and by immunocytochemistry. The immunological and biochemical characterization of biotinylated β-hexosaminidase A revealed that the plasma membrane associated enzyme is fully processed, suggesting its lysosomal origin.
Intrathyroidal feedforward and feedback network regulating thyroid hormone synthesis and secretion
2022, Frontiers in Endocrinology

View all citing articles on Scopus

¹⁾: Dr. Peter Lemansky, Institut für Zellbiologie und Bonner Forum Biomedizin, Ulrich-Haberland-Str. 61a, D-53121 Bonn/Germany.

View full text

Iodination of mature cathepsin D in thyrocytes as an indicator for its transport to the cell surface

Abstract

J. Biol. Chem

Major sites of cleavage by cathepsins B, D and L. J. Biol. Chem

J. Biol. Chem

Biochim. Biophys. Acta

J. Biol. Chem

Trends Cell Biol

J. Biol. Chem

J. Biol. Chem

J. Biol. Chem

J. Biol. Chem

Cell

J. Biol. Chem.

J. Biol. Chem

J. Biol. Chem

V On the redistribution of cytosomes following stimulation with thyrotropic hormone. J. Ultrastruct. Res

Cycling of two endogenous lysosomal membrane proteins, lamp-2 and acid phosphatase, between the cell surface and lysosomes in cultured rat hepatocytes

J. Biochem. (Tokio)

Multimerization of thyroglobulin (TG) during extracellular storage: Isolation of highly cross-linked TG from human thyroids

J. Clin. Endocrinol. Metab

Lysosomal acid phosphatase is transported to lysosomes via the cell surface

EMBO J

Extrathyroidal release of thyroid hormones from thyroglobulin by J774 mouse macrophages

J. Clin. Invest

Evidence for extracellularly acting cathepsins mediating thyroid hormone liberation in thyroid epithelial cells

Endocrinology

Degradation of extracellular-matrix proteins by human cathepsin B from normal and tumor tissues

Biochem. J

Corrective factors for inborn errors of mucopolysaccharide metabolism

Methods Enzymol

Proteolytic processing of cathepsin D in prelysosomel organelles

Eur. J. Cell Biol

Purification of lysosomal membrane proteins from human placenta

Eur. J. Cell Biol

Thyroglobulin (Tg) hydrolysis starts in prelysosomes

Cysteine proteinases from human thyroids and their action on thyroglobulin

Endocrinology

Site of iodination in the rat thyroid gland deduced from electron microscopic autoradiographs

Endocrinology