Figure 1: A catalog of spidroin genes from the golden orb-weaver spider.

Phylogenetic tree showing the evolutionary relationship among the assembled N. clavipes spidroins using N-terminal sequences (∼130 residues) from each putative gene product (bootstrap values provided in Supplementary Fig. 3a). Circular symbols denote the silk class—with putative functional application and presumed gland of origin (Supplementary Fig. 1b,c)—of each spidroin, determined by alignment to known spidroin sequences (spidroins that did not cluster are designated “unknown”). Genic structures are drawn to scale. N-terminal domains are colored green, and C-terminal domains are colored red. The illustration of the arrays of repeated motifs found within the internal coding regions is simplified, symbolized by alternating light and dark gray bars. Non-repetitive coding 'spacer' sequences (pink), scaffold gaps (black bars), 'linked' scaffolds validated by long-range PCR (string of “NNNNN”), and flanking noncoding or intronic sequences (thin lines and arrows) are also shown.