76 – Endogenous RNA-Bound RNA Dependent DNA Polymerase Activity in Neurospora crassa

Authors : K. DUTTA, M. BELJANSKI, P. BOURGAREL
Botany Department, Howard University, Washington, DC
Exp. Mycology, 1977, 1, pp. 173-182.

Available in English only

ABSTRACT: Evidence indicating the presence of a RNA-bound RNA-dependent DNA polymerase (RDDP) in the eukaryotic fungus Neurospora crassa is presented. This enzyme, free of DNA-dependent DNA polymerase, is capable of synthesizing DNA only in the presence of all four deoxyribonucleoside 5′-triphosphates and Mg2+. The DNA polymerase activity is decreased considerably if the RNA bound to the enzyme is eliminated. The activity can be restored by addition of some particular RNA but not by addition of DNA. Both template RNA and the synthesized DNA product sedimented on sucrose density gradients are approximately 6 S. RNA-bound RNA-dependent DNA polymerase partially purified from extracts of N. crassa was distinguishable from known DNA-dependent DNA polymerases. DNA synthesized by RDDP was acid-precipitable and complementary to enzyme-bound RNA.

Download Endogenous RNA-Bound RNA Dependent DNA Polymerase Activity in Neurospora crassa

75 – Particular small size RNA and RNA fragments from different origins as tumor inducing agents in Datura stramonium

Authors : M. BELJANSKI, Y. AARON-DA-CUNHA
Molecular Biology Reports, 1976, 2, pp. 497-506.

Available in English only

ABSTRACT: Particular RNA fragments obtained by action of pancreatic ribonuclease on purified RNAs originating from species totally unrelated to Agrobacterium tumefaciens (Escherichia coli, rabbit, monkey) are capable if inducing the formation of transplantable tumorous tissue when introduced at wounded sites in inverted stems of Datura stramonium maintained under axenic conditions on a medium containing auxin and kinetin. Reovirus RNA and a small size RNA (5-6 S) isolated from RNA bound RNA directed DNA polymerase from Escherichia coli also induced the appearance of tumorous tissues which grow on solid synthetic medium in the absence of auxin and kinetin.

Download Particular small size RNA and RNA fragments from different origins as tumor inducing agents in Datura stramonium

71 – ARN-amorceurs riches en nucléotides G et A indispensables à la réplication in vitro de l’ADN des phages QX174 et lambda (_)

Authors : M. BELJANSKI
C.R. Acad. Sci., 1975, 280, pp. 1189-1192 (série D).

Available in French only

ABSTRACT: Les ARN-fragments riches en nucléotides G et A déclenchent en présence d’ADN polymérase ADN dépendante I, la réplication de l’ADN circulaire simple chaîne du phage ΦX 174 en double chaîne ou forme réplicative ainsi que celle de l’ADN du pahge λ.

Download ARN-amorceurs riches en nucléotides G et A indispensables à la réplication in vitro de l’ADN des phages ΦX 174 et lambda

70 – ARN-fragments inhibiteurs “in vivo” de la multiplication des virus du fibrome de Shope et de la vaccine

Authors : M. BELJANSKI, L. CHAUMONT, C. BONISSOL, M. S. BELJANSKI
C.R. Acad. Sci., 1975, 280, pp. 783-789 (série D).

Available in French only

ABSTRACT: Parmi plusieurs ARN-fragments isolés après dégradation des ARN ribosomiques (E.coli M500 Sho-R), seuls certains de ceux obtenus par l’action de la ribonucléase pancréatique inhibent complètement chez le lapin la multiplication des virus du fibrome de Shope et la vaccine, sans compromettre la vie de l’animal.

Download ARN-fragments inhibiteurs “in vivo” de la multiplication des virus du fibrome de Shope et de la vaccine

69 – ARN-fragments, amorceurs nécessaires à la réplication ” in vitro ” des ADN

Authors : M. BELJANSKI, M. S. BELJANSKI, M. PLAWECKI, P. MANIGAULT
C.R. Acad. Sci., 1975, 280, pp. 363-366 (série D).

Available in French only

ABSTRACT: Les ARN-fragments obtenus par dégradation ménagée des ARN ribosomiques (E. coli K12) en présence de ribonucléases, agissent avec une certaine spécificité comme amorceurs dans la réplication in vitro des ADN d’origines différentes. Ces résultats rendent possible de prévoir dans une large mesure l’action éventuelle des ARN-fragments particuliers dans le processus de la réplication in vivo des ADN. L’introduction dans une cellule déréglée d’ARN-fragments exogènes pourrait permettre à cette cellule de retrouver sa physiologie normale.

Download ARN-fragments, amorceurs nécessaires à la réplication ” in vitro ” des ADN

68 – Genetic transformation of Agrobacterium tumefaciens B6 by RNA and nature of the tumor-inducing principle

Authors : M. BELJANSKI, P. MANIGAULT, M.S. BELJANSKI, Y. AARON-DA-CUNHA
First International Congress of the International Association of Microbiology Soc. Tokyo I.A.M.S., 1974,1, pp. 131-141.

Available in English only

ABSTRACT: The fact that TI-RNA was found to be present in oncogenic and non-oncogenic strains of A. tumefaciens suggests that it is not released in biologically active form from the non-oncogenic strains and that the oncogenic strains have some special mechanisms for introducing the TI-RNA into host cells that is not possessed by the avirulent strains.

Download Genetic transformation of Agrobacterium tumefaciens B6 by RNA and nature of the tumor-inducing principle

67 – RNA-Bound Reverse Transcriptase in Escherichia coli and in Vitro Synthesis of a Complementary DNA

Authors : M. BELJANSKI, M. S. BELJANSKI
Biochemical genetics, 1974, 12, pp. 163-180.

Available in English only

ABSTRACT: RNA-bound reverse transcriptase can be easily distinguished from RNA-free reverse transcriptase and DNA-dependent DNA polymerase after fractionation of extracts from Escherichia coli on a DEAE-cellulose column. This enzyme is capable of synthesizing a DNA-like product in the absence of exogenously added template provided that all four deoxyribonucleoside 5′-triphosphates are present in the incubation mixture. Removal of RNA from the enzyme by RNase leads to a considerably decreased polymerizing activity. The activity can be restored under appropriate conditions either by RNA originating from the enzyme or by transforming RNA excreted by showdomycin-resistant E. coli. Enzyme-bound RNA has several characteristics already found for the transforming RNA. DNA synthesized by RNA-bound reverse transcriptase is complementary to the enzyme-bound RNA.

Download RNA-Bound Reverse Transcriptase in Escherichia coli and in Vitro Synthesis of a Complementary DNA

66 – Isolation of the Tumor-Inducing RNA from Oncogenic and Nononcogenic Agrobacterium tumefaciens

Authors : M. BELJANSKI, Y. AARON-DA-CUNHA, M.S. BELJANSKI, P. MANIGAULT, P. BOURGAREL
Proc. National Acadademy of Science (USA), 1974, 71, pp. 1585-1589.

Available in English only

ABSTRACT: Two RNA fractions have been isolated and purified from both oncogenic and nononcogenic strains of Agrobacterium tumefaciens. Both RNAs are capable of inducing the formation of transplantable tumors when introduced at wound sites in stems of Datura stramonium plants. One of these RNA fractions was found to be bound to an RNA-directed DNA polymerase, while the other was associated with the bacterial DNA. Physical evidence suggests that both are single stranded and small in size; linear sucrose gradients show that their size corresponds to a value of 5-6 S. A concentration of 4-5 ug of the RNAs dissolved in 0.01 ml of water is effective in initiating the formation of transplantable tumors in Datura plants.

Download Isolation of the Tumor-Inducing RNA from Oncogenic and Nononcogenic Agrobacterium tumefaciens

65 – Synthèse in vitro d’un ARN utilisé comme amorceur pour la réplication de l’ADN

Authors : M. BELJANSKI, PLAWECKI
C.R. Acad. Sci., 1974, 278, pp. 1413-1416 (série D).

Available in French only

ABSTRACT: Nous montrons ici que, in vitro, la PNPase des bactéries sauvages d’E. coli synthétise à 70° un ARN (ARN-70°) que l’ADN polymérase ADN dépendante d’origine bactérienne utilise comme amorceur pour la synthèse des nouvelles chaînes d’ADN.

Download Synthèse in vitro d’un ARN utilisé comme amorceur pour la réplication de l’ADN

64 – Transforming RNA as a template directing RNA and DNA synthesis in bacteria

Authors : M. BELJANSKI, M. PLAWECKI
In Niu and Segal (eds), The Role of RNA in reproduction and development. North Holland Publ.Co., 1973, pp.203-224.

Available in English only

ABSTRACT: Attempts were made to approach the mechanism by which the transfer of information is carried by transforming RNA from Escherichia coli. Transforming RNA, capable of inducing inherited changes in recipient cells, is used in vitro as a template by two distinct enzymes which mediate the transfer of information from RNA to RNA and DNA respectively. Using transforming RNA as a template, polynucleotide phosphorylase insensitive to rifampicin, synthesizes a product which was characterized as being a “copy” of template RNA. Reverse transcriptase, which can be physically separated from DNA polylerase, transcribes the transforming RNA into a complementary DNA product. According to hybridization experiments, DNA from Agrobacterium tumefaciens transformed by E. coli transforming RNA seems to contain one or less than one copy of complementary DNA.

Download Transforming RNA as a template directing RNA and DNA synthesis in bacteria

63 – Séparation de la transcriptase inverse de l’ADN polymérase ADN dépendante. Analyse de l’ADN synthétisé sur le modèle de l’ARN transformant

Authors : M. BELJANSKI
C.R. Acad. Sci., 1973, 276, pp. 1625-1628 (série D).

Available in French only

ABSTRACT: Nous démontrons ici que la transcriptase inverse, aisément séparable de l’ADN polymérase ADN dépendante chez E. coli sauvage ou mutant sho-R, se trouve sous 2 formes : libre et associée à un ARN. L’ADN synthétisé par la transcriptase inverse a été analysé.

Download Séparation de la transcriptase inverse de l’ADN polymérase ADN dépendante. Analyse de l’ADN synthétisé sur le modèle de l’ARN transformant