Physicochemical Characterization of Adeno-associated Satellite Virus Type 4 and Its Nucleic Acid

Abstract

Based on protein, deoxyribonucleic acid (DNA), and phosphorus analyses, adenoassociated satellite virus type 4 has a DNA content of 26.5%, significantly larger than type 1 which contains 18.9% DNA. Type 4 DNA contains 58 to 62% guanine + cytosine, as calculated from thermal denaturation temperature and buoyant density measurements. Simian adenovirus SV15, which serves as a helper virus for type 4 satellite, contains 13.7% DNA with a guanine + cytosine content of 55 to 57%. The DNA extracted from type 4 satellite virus is a linear, double-stranded molecule, as shown by thermal denaturation temperature profile measurements and by electron microscopy. The contour length and sedimentation coefficient of type 4 DNA indicate a molecular weight of 3.0 X 106 daltons.

Adenovirus-Associated Virus Multiplication IX. Extent of Transcription of the Viral Genome In Vivo

“…Since the molecular weight of single-stranded AAV DNA is approximately 1.5 x 101 (16,18), transcription of 70 to 80%-of the minus strand would yield RNA species with a total molecular weight of about 1.1 X 106. It was previously shown that AAV RNA synthesized in vivo was mainly composed of molecules having a mean molecular weight of 7.5 x 105 (8).…”

“…In addition, we have observed that the AAV RNA synthesized in the presence of either helper virus contains similar nucleotide sequences and has a mean molecular weight of approximately 7.5 x 105 (8). An RNA species of this size is equivalent to about 50%7o of the AAV DNA minus strand of which the molecular weight is approximately 1.5 x 106 (16,18). Whether one or more AAV RNA species with a molecular weight of 7.5 X 105 might be synthesized in vivo was uncertain because the actual extent of the minus strand transcription was not known.…”

Structural Proteins of Adenovirus-Associated Viruses

“…The single-stranded AAV genome has a molecular weight of 1.5 x 106 to 1.7 x 106 daltons (15,19,21) and is approximately 112 as large as the double-stranded adenovirus genome. Although AAV are defective, AAV DNA is similar in size to DNA from other parvoviruses (4,22).…”

Separation of Two Types of Adeno-Associated Virus Particles Containing Complementary Polynucleotide Chains

“…Purified adeno-associated virus (AAV) deoxyribonucleic acid (DNA) has been characterized as a double-stranded molecule with a molecular weight of 3.0 to 3.6 X 106 daltons (5,7). However, AAV DNA is single-stranded within the virion (1,4) and, after release, complementary single strands from different particles base-pair to form a double helix (6).…”