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We have cloned a murine cDNA whose deduced sequence encodes a 455-amino-acid (aa) zinc-finger protein (Zfp), PZf (penta Zf protein). Sequence analysis shows that PZf has multiple phosphorylation consensus sites for casein kinase II and protein kinase C in its N-terminal portion. This region (aa 1 to 197), which does not share significant homology to known aa sequences, has a number of charged (39 Glu, 15 Asp, 23 Lys, 22 Arg) and hydroxyl (20 Ser, 12 Thr) aa. This potentially phosphorylatable region is followed by five C2H2 Zf in the middle of the protein. The Pzf gene is transcribed as a 5-kb mRNA in all murine tissues examined. The human genome also seems to contain one or more Pzf-related genes.

The genes encoding body-wall-specific glyceraldehyde-3-phosphate dehydrogenase from Caenorhabditis briggsae were sequenced and compared to the homologous genes from Caenorhabditis elegans. The direct tandem organization of these genes, gpd-2 and gpd-3, and the size and location of the two introns m each gene are the same in C. elegans and C. briggsae. Primer-extension studies demonstrated that the two genes in C. briggsae are trans-spliced differentially with the same splice leader (SL) RNAs as are observed in C. elegans. The gpd-2 gene is trans-spliced with SL1 while gpd-3 is trans-spliced with SL2. Significant sequence conservation was observed within the promoter regions of each species and may indicate those regions responsible for body-wall-muscle-specific gene expression and/or differential trans-splicing. Comparisons of the sequences suggest that the tandem repeat of the genes has been subjected to concerted evolution and that C. briggsae and C. elegans diverged much earlier than would be anticipated based on morphological similarities alone. Finally, an open reading frame found several hundred nucleotides upstream from gpd-2, in both species, appears to be homologous to the ATP synthase subunit, ATPase inhibitor protein, from bovine mitochondria.

Collagen genes col-6, col-7 (partial), col-8, col-14 and col-19 from the nematode Caenorhabditis elegans were sequenced, and compared to the previously sequenced genes col-1 and col-2. The genes are between 1.0 and 1.2 kb in length, and each includes one or two short introns. The presumptive promoter regions contain sequences similar to the eukaryotic TATA promoter element. Two distinct, conserved sequences were found in the presumptive promoter regions of, respectively, the dauer larva-specific genes col-2 and col-6, and the primarily adult-specific genes col-7 and col-19. The domain structures of the collagen polypeptides are similar: each polypeptide contains two triple-helix forming (Gly-X-Y)n domains, one of 30–33 amino acids (aa), and the other of 127–132 aa. The latter domain is interrupted by one to three short (2–8 aa) non-(Gly-X-Y)n segments that occur at relatively conserved locations in each polypeptide. Sets of cysteine residues flank the (Gly-X-Y)n domains in all of the polypeptides. The genes can be placed into three families based upon amino acid sequence similarities. Genes within a family do not always exhibit similar developmental expression programs, suggesting that structural and regulatory regions of the genes have evolved separately. The codon usage in the genes is highly asymmetrical, with adenine appearing in the third position of 85% of the glycine codons, and 93% of the proline codons.