Identification and properties of a receptor for the invertebrate  cytokine astakine, involved in hematopoiesis.
We have recently isolated an invertebrate cytokine from a freshwater crayfish, which we named astakine 1. Interestingly this protein is expressed exclusively in hemocytes and hematopoietic tissue and is essential for the release of new hemocytes into the open circulatory system of these animals. This astakine has a prokineticin (PK) domain but lacks the N-terminal AVIT amino acids and hence receptor binding may differ from vertebrate PKs. Accordingly, here we report that a receptor for astakine 1 on hematopoietic tissue (Hpt) cells is identical to the beta-subunit of F1ATP synthase. In this study we have used several different methods to clearly demonstrate that ATP-synthase is located on the plasma membrane of a subpopulation of Hpt cells and there may function as a receptor for astakine, whereas mature blood cells (hemocytes) do not have any ATP-synthase on the outside of their plasma membranes. Our results clearly show that ATP synthase beta subunits are present on the cell surface of Hpt cells and highlight the need for more detailed studies on intracellular traffic connections between mitochondria and other membrane compartments.
Lin
Xionghui
X
Department of Comparative Physiology, Uppsala University, Uppsala, Sweden.
Kim
Young-A
YA
Lee
Bok Luel
BL
Söderhäll
Kenneth
K
Söderhäll
Irene
I
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D003400:Astacoidea / Q000737:chemistry*; D002478:Cells, Cultured; D003432:Cross-Linking Reagents / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D006410:Hematopoiesis / Q000502:physiology*; D006434:Hemocytes / Q000166:cytology / Q000502:physiology; D006801:Humans; D025261:Mitochondrial Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D042662:Vascular Endothelial Growth Factor, Endocrine-Gland-Derived / Q000235:genetics / Q000378:metabolism*
D003432:Cross-Linking Reagents; D016207:Cytokines; D021122:Protein Subunits; D011956:Receptors, Cell Surface; D042662:Vascular Endothelial Growth Factor, Endocrine-Gland-Derived; C501708:astakine protein, Pacifastacus leniusculus; D000255:Adenosine Triphosphate; C474451:F1F0-ATP synthase; D025261:Mitochondrial Proton-Translocating ATPases