Progressive alteration in the pattern of nucleic acid metabolism in the newt iris in cultivation

✍ Scribed by Jauker, Fritz ;Yamada, Tuneo

• Book ID: 102335864
• Publisher: John Wiley and Sons
• Year: 1973
• Tongue: English
• Weight: 495 KB
• Volume: 183
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1401830203

✦ Synopsis

Abstract

The dorsal iris of the adult newt (Notophthalmus viridescens) was cultured in vitro for periods up to 12 days and then exposed to [^3^H] uridine. Labeled RNA extracted from the tissue was studied on a sucrose density gradient. The profiles indicate that incorporation into ribosomal RNA's is progressively increased during the first four days and progressively decreased during the following days. Incorporation into the precursor of ribosomal RNA is also progressively decreased in the later phase. Compared with ribosomal RNA's and their precursor, an RNA fraction with an S value higher than 40 is less affected. A study of incorporation of [^3^H] thymidine into the trichloroacetic acid‐insoluble fraction of the same tissue cultured in vitro showed a wave of incorporation beginning on day 4 and persisting to the end of the culture period. The data were compared with data obtained for the same tissue left in situ after lentectomy, which depigments and forms a lens.