Insights on the structure and stability of Licanantase: a trimeric acid-stable coiled-coil lipoprotein fromAcidithiobacillus thiooxidans

The tubular network of the endoplasmic reticulum (ER) is formed by connecting ER tubules through three-way junctions. Two classes of the conserved ER membrane proteins, atlastins and lunapark, have been shown to reside at the three-way junctions so far and be involved in the generation and stabilization of the three-way junctions. In this study, we report TMCC3 (transmembrane and coiled-coil domain family 3), a member of the TEX28 family, as another ER membrane protein that resides at the three-way junctions in mammalian cells. When the TEX28 family members were transfected into U2OS cells, TMCC3 specifically localized at the three-way junctions in the peripheral ER. TMCC3 bound to atlastins through the C-terminal transmembrane domains. A TMCC3 mutant lacking the N-terminal coiled-coil domain abolished localization to the three-way junctions, suggesting that TMCC3 localized independently of binding to atlastins. TMCC3 knockdown caused a decrease in the number of three-way junctions and expansion of ER sheets, leading to a reduction of the tubular ER network in U2OS cells. The TMCC3 knockdown phenotype was partially rescued by the overexpression of atlastin-2, suggesting that TMCC3 knockdown would decrease the activity of atlastins. These results indicate that TMCC3 localizes at the three-way junctions for the proper tubular ER network.

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Seasonal dynamics of zooplankton resource use revealed by carbon amino acid stable isotope values

Marine Ecology Progress Series ◽

10.3354/meps11319 ◽

2015 ◽

Vol 531 ◽

pp. 143-154 ◽

Cited By ~ 6

Author(s):

JM Nielsen ◽

M Winder

Keyword(s):

Amino Acid ◽

Stable Isotope ◽

Resource Use ◽

Seasonal Dynamics ◽

Acid Stable

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Co-purification of bone resorbing activity and adenylate cyclase stimulating activity from human tumours associated with the humoral hypercalcaemia of malignancy

Acta Endocrinologica ◽

10.1530/acta.0.1140018 ◽

1987 ◽

Vol 114 (1) ◽

pp. 18-26 ◽

Cited By ~ 5

Author(s):

Chohei Shigeno ◽

Itsuo Yamamoto ◽

Shegiharu Dokoh ◽

Megumu Hino ◽

Jun Aoki ◽

...

Keyword(s):

Bone Resorption ◽

High Performance ◽

Basic Protein ◽

Gel Filtration ◽

Exchange Chromatography ◽

Protein Factor ◽

Human Tumours ◽

Acid Stable ◽

Bone Resorbing Activity

Abstract. We have partially purified a tumour factor capable of stimulating both bone resorption in vitro and cAMP accumulation in osteoblastic ROS 17/2 cells from three human tumours associated with humoral hypercalcaemia of malignancy. Purification of tumour factor by sequential acid urea extraction, gel filtration and cation-exchange chromatography, reverse-phase high performance liquid chromatography followed by analytical isoelectric focussing provided a basic protein (pI > 9.3) with a molecular weight of approximately 13 000 as a major component of the final preparation which retained both the two bioactivities. Bone resorbing activity and cAMP-increasing activity in purified factor correlated with each other. cAMP-increasing activity of the factor was heat- and acid-stable, but sensitive to alkaline ambient pH. Treatment with trypsin destroyed cAMP-increasing activity of the factor. Synthetic parathyroid hormone (PTH) antagonist, human PTH-(3– 34) completely inhibited the cAMP-increasing activity of the factor. The results suggest that this protein factor, having its effects on both osteoclastic and osteoblastic functions, may be involved in development of enhanced bone resorption in some patients with humoral hypercalcaemia of malignancy.

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