Coding capacity

Molecular characterization of the coding capacity of the MHS4 region on chromosome 3ql3.1 M. Roche, Jena University T. Duffel, Jena University... 

The plastid genome of modern higher plants remains well conserved, with little interspecific variation in genomic organization and coding capacity. Identical copies of the plastid genome are present in a diverse array of plastid transformation types proplastids (precursor plastids found in most plant cells and present predominantly in meristematic tissues). 

Certain pre-mRNAs contain more than one set of signal sequences for 3 end cleavage and polyadenylation. In some cases, the location of the alternative polyadenylation sites is such that, depending on the site chosen, particular exons may be lost or retained in the subsequent splicing reactions (Fig. 7). Here the effect is to change the coding capacity of the final mRNA so that different proteins are produced depending on the polyadenylation site used. In other... 

Fig. 8. Alternative RNA splicing pathways. In the simple example shown, the transcript can be spliced by alternative pathways leading to two mRNAs with different coding capacities, i.e. exons 1, 2 and 3 or just exons 1 and 3. For genes containing many exons, a substantial number of alternative splice pathways may exist which are...

Akman L, Rio RV, Beard CB, Aksoy S. Genome size determination and coding capacity of Sodalis glossinidius, an enteric symbiont of tsetse flies, as revealed by hybridization to Escherichia coli gene arrays. J. Bacteriol. 2001 183 4517-4525. Beard CB, O Neill SL, Mason P, Mandelco L, Woese CR, Tesh RB, Richards FF, Aksoy S. Genetic transformation and phylogeny of bacterial symbionts from tsetse. Insect Mol. Biol. 1993 1 123-131. 

Compare the sizes and coding capacity of prokaryotic genomes with those of eukaryotes. What other features distinguish them ... 

The Size and Coding Capacity of mtDNA Vary Considerably in Different Organisms... 

Differences in the size and coding capacity of mtDNA from various organisms most likely reflect the movement of DNA between mitochondria and the nucleus during evolution. Direct evidence for this movement comes from the observation that several proteins encoded by mtDNA in some species are encoded by nuclear DNA In others. It thus appears that entire genes moved from the mitochondrion to the nucleus, or vice versa, during evolution. 

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