Optimization of Spider Silk Glands for the Elicited Production of a Tissue‐Specific Fibroin Product

Through simple manipulations, we have been able to virtually abolish the production of a fibroin by a pair of spider glands, and subsequently elicit the process to a high level of production. The response, monitored through time sequence, has revealed that fibroin production by the large ampullate glands of the spider Nephila clavipes is the culmination of a series of time and tissue‐specific events, which optimize the glands for their highly demanding function. At sixty minutes prior to the production of the full‐size product, the glands are enriched in the fibroin’s template. Shortly after, the glands are enriched in the tRNAs cognate to the fibroin’s predominant amino acids, achieving an adaptive shift in the gland’s tRNA population. The earliest of the responses, one of considerable magnitude, provides the glands with a wide variety of small RNAs. Among these, we have, thus far, identified a tissue‐specific alanine tRNA of, as yet, unknown function, but of interest because it has been found to be a constituent of the silk production strategy of the silk worm. Two isoforms of 5S rRNA are also provided to the glands within this early event. Our last incursion has revealed that all members of the U subset of small nuclear RNAs, which constitute the spliceosome complex, including isoforms of U1 and U2, are upgraded during this early event, thus optimizing the gland’s tissues with early components of the protein synthesis machinery.