Molecular cloning and characterization of arginine-specific ADP-ribosyltransferases from chicken bone marrow cells

Among a number of tissues and peripheral blood cells in chicken, leukocytes, bone marrow cells, liver and spleen showed high ADP-ribosyltransferase activity, with leukocytes having the highest. Density gradient centrifugation of the leukocytes revealed that the leukocyte ADP-ribosyltransferase originates in the polymorphonuclear cells, so called heterophils. Subcellular distribution of the cells showed the localization of the enzyme in the granule fraction. Based on the obtained amino acid sequences of arginine-specific ADP-ribosyltransferase purified from chicken peripheral heterophils, two arginine-specific ADP-ribosyltransferase cDNAs (designated AT1 and AT2) were obtained from chicken bone marrow cells. Each cDNA encodes a different peptide of 312 amino acid residues. Homology of the deduced amino acid sequences between AT1 and AT2 was 78.3%. Arginine-specific ADP-ribosyltransferase activity was detected in culture medium of COS 7 cells transiently transfected with AT1 cDNA, while activity from the cells transfected with AT2 cDNA was found in both culture medium and cell lysate. AT1 transferase required 2-mercaptoethanol (MSH) for the activity and in the presence of NaCl, the activity was inhibited while the AT2 enzyme was activated by either agent. Highly conserved regions were observed among the deduced amino acid sequences of AT1, AT2, chicken erythroblast and rabbit and human skeletal muscle ADP-ribosyltransferases, and rodent T-cell surface antigen RT6. Two forms of the transferase with much the same properties as AT1 and AT2 proteins, regarding the effect of NaCl and MSH, were detected in bone marrow cells. Based on these results it seems that AT1 and AT2 cDNAs encode the two forms of arginine-specific ADP-ribosyltransferase detected in chicken bone marrow cells.

A newly identified glycosylphosphatidylinositol-anchored arginine-specific ADP-ribosyltransferase in chicken spleen

An arginine-specific ADP-ribosyltransferase activity was detected in chicken spleen membrane fraction using a capillary electrophoresis assay and the activity was extracted by phosphatidylinositol-specific phospholipase C but not by 1 M NaCl or 1% Triton X-100. The enzyme protein was purified from chicken spleen membrane fraction to apparent homogeneity with a six-step method containing phosphatidylinositol-specific phospholipase C treatment, ammonium sulfate precipitation and conventional column chromatographies. Apparent molecular mass of the purified enzyme estimated with SDS/PAGE was 44 kDa. N-glycanase treatment of the enzyme reduced the apparent molecular size on SDS/PAGE. The enzyme was recognized by anti-cross reacting determinant antibodies. Partial amino acid sequence of the purified enzyme protein showed high homologies with primary structures of previously reported chicken arginine-specific ADP-ribosyltransferases.

Detection of arginine-ADP-ribosylated protein using recombinant ADP-ribosylarginine hydrolase

We made use of ADP-ribosylarginine hydrolase to detect arginine-ADP- ribosylated proteins. The hydrolase was expressed in Escherichia coli as a protein fused with glutathione S-transferase (GST). The fusion protein GST-ADP-ribosylarginine hydrolase catalyzed the hydrolysis of alpha-ADP-ribosylarginine to produce ADP-ribose and arginine. Casein ADP-ribosylated with [32P]NAD and chicken heterophil arginine-specific ADP-ribosyltransferase served as a substrate for the recombinant ADP-ribosylarginine hydrolase and the released ADP-ribose was determined. Protein ADP-ribosylated by cholera toxin could serve as substrate of the hydrolase but protein ADP-ribosylated by pertussis toxin, diphtheria toxin, or C(3) enzyme of Clostridium botulinum could not. The hydrolase did not release the radioactivity incorporated into isolated rat liver nuclei incubated with [(32)P]NAD or in bovine brain cytosol incubated with [(32)P]ADP-ribose. In homogenate of mouse heart which contained arginine-specific ADP-ribosyltransferase, labeling of a 55-kDa protein by incubation with [(32)P]NAD was removed by ADP-ribosylarginine hydrolase treatment; hence, the specific hydrolysis of ADP-ribose-arginine bond by GST-ADP-ribosylarginine hydrolase can be used to detect the arginine-ADP-ribosylated proteins in crude preparations. Arginine--ADP-ribosylated proteins in crude preparations. Arginine-ADP-ribosylated proteins in mouse spleen lymphocytes were identified using this method.

A newly identified GPI-anchored arginine-specific ADP-ribosyltransferase activity in chicken spleen

Arginine-specific ADP-ribosyltransferase activity was detected in chicken spleen membrane fraction and the activity was extracted by phosphatidylinositol-specific phospholipase C but not by 1 M NaCl or 1% Triton X-100. The transferase activity extracted from the spleen membrane was thiol-independent and was not inhibited by 200 mM NaCl. Zymographic analysis of the transferase, under non-reducing conditions, showed two forms of active bands corresponding to a molecular mass of 46 and 42 kDa. Thus, the presence of this novel arginine-specific ADP-ribosyltransferase, anchored to the membrane through glycosylphosphatidylinositol and different from previously cloned chicken transferases, AT1 and AT2, is being given further attention.

Assay of arginine-specific adenosine-5'-diphosphate-ribosyltransferase by capillary electrophoresis

Using high-voltage capillary electrophoresis we detected ADP-ribosylarginine, a product of ADP-ribosylation reaction catalyzed by arginine-specific ADP-ribosyltransferase in the presence of NAD and L-arginine. The authentic ADP-ribosylarginine, detected by its ultraviolet absorbance at 254 nm, had a different retention time from NAD or nicotinamide. When the ADP-ribosylation reaction products were analyzed, the peak corresponding to ADP-ribosylarginine increased with incubation time and in an enzyme-dose-dependent manner. The lower limit of detection was 0.3 pmol, a value 100 times lower than that obtained with the reversed-phase high-performance liquid chromatography assay described previously. Using the capillary electrophoresis system, a thiol-independent ADP-ribosyltransferase activity was detected in chicken spleen cell membrane. Since the capillary electrophoresis assay for ADP-ribosylarginine is simpler, faster, and less expensive than the high-performance liquid chromatography assay, determination of arginine-specific ADP-ribosyltransferase activity in animal tissues will be facilitated.

Cloning and expression of cDNA for arginine-specific ADP-ribosyltransferase from chicken bone marrow cells

Two arginine-specific ADP-ribosyltransferase cDNAs (designated AT1 and AT2) were cloned from chicken bone marrow cells. Each cDNA encodes a different peptide of 312 amino acid residues. Homology of deduced amino acid sequences between AT1 and AT2 was 78.3%. We found all six combined peptide sequences of 222 amino acid residues derived from purified chicken heterophil ADP-ribosyltransferase (Mishima, K., Terashima, M., Obara, S., Yamada, K., Imai, K., and Shimoyama, M. (1991) J. Biochem. (Tokyo) 110, 388-394) in the deduced amino acid sequence of AT1, with two amino acid mismatches. Arginine-specific ADP-ribosyltransferase activity was detected in culture medium of COS 7 cells transiently transfected with AT1 cDNA, while activity from the cells transfected with AT2 cDNA was found in both culture medium and cell lysate. AT1 transferase required 2-mercaptoethanol for the activity. The activity was inhibited in the presence of NaCl while AT2 enzyme was activated by either agent. On zymographic in situ gel analysis, estimated molecular masses of the AT1, AT2 and purified chicken heterophil transferases were 32, 34, and 27.5 kDa, respectively. Northern blot analysis with specific probes to AT1 or AT2 cDNAs revealed about a 1.5-kilobase message in chicken bone marrow cells but no signals were observed in heterophils, spleen, and liver of chicken or human HL-60 cells. Highly conserved regions were observed among the deduced amino acid sequences of AT1, AT2, rabbit skeletal muscle transferase, and rodent T-cell surface antigen RT6s.

Localization of an endogenous ADP-ribose acceptor, p33, in polymorphonuclear cell granules in chicken liver interlobular connective tissue

We investigated immunohistochemically the localization of p33, an endogenous substrate protein for an arginine-specific ADP-ribosyltransferase in chicken liver. Polymorphonuclear-pseudo-eosinophilic granulocytes (heterophils) in interlobular connective tissues of the liver were exclusively and strongly stained with the antibody against p33. Strong reactivity was associated with granules in cytoplasm of the heterophils. When the chicken liver nuclear fraction was washed, the transferase activity was released into the 600 x g supernatant fraction while a nuclear enzyme poly(ADP-ribose) synthetase was retained in the pellet fraction. These results indicate that p33 and probably also ADP-ribosyltransferase, found in the liver nuclear fraction [Tanigawa et al. (1984) J. Biol. Chem. 259, 2022-2029, Mishima et al. (1988) Eur. J. Biochem. 179, 267-273], originate from interlobular heterophils of the chicken liver.