Open AccessTranslation in vivo and in vitro of mRNAs Coding for Vitellogenin, Serum Albumin and Very‐Low‐Density Lipoprotein II from Chicken Liver
Author(s) -
WIERINGA Bé,
ZWAAGGERRITSEN Janneke,
MULDER Janny,
AB Geert,
GRUBER Max
Publication year - 1981
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1981.tb05191.x
Subject(s) - vitellogenin , polysome , reticulocyte , messenger rna , biology , in vivo , protein biosynthesis , microbiology and biotechnology , vitellogenins , ribosome , biochemistry , rna , gene , embryo , vitellogenesis , oocyte
Characterisation of polysomes from estrogenized chicken liver revealed that very‐low‐density lipoprotein II (VLDL II ), serum albumin and vitellogenin mRNAs are differently packed with ribosomes during translation in vivo . The ribosome density per number of nucleotides is high for VLDL II mRNA, intermediate for serum albumin mRNA and low for vitellogenin mRNA. This difference in ribosomal load is maintained throughout the period of hormone effect. The differential utilisation observed for vitellogenin and VLDL II mRNAs partly explains the large difference in molar production rate between these yolk protein precursors. Translation properties and efficiency of the three hepatic mRNAs were also compared in the mRNA‐depleted reticulocyte lysate. Elongation of the nascent chains for vitellogenin and serum albumin proceeded in a discontinuous fashion. Initiation in vitro was studied at varying ionic strengths, in the presence of aurintricarboxylic acid, and at suboptimal hemin concentrations. VLDL II mRNA expression is by far the most resistant to 7‐methylguanosine 5′triphosphate (m 7 GTP) and high salt concentrations, vitellogenin mRNA the least. This behaviour resembles the differential utilisation of the mRNAs in vivo . The putative structural basis of these differences is discussed.