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Updated: May 24, 2026
09:47
Microdissection of Black Widow Spider Silk-producing Glands
Published on: January 11, 2011
Variation in protein intake induces variation in spider silk expression
Sean J Blamires1, Chun-Lin Wu, I-Min Tso
1Department of Life Science, Tunghai University, Taichung, Taiwan.
Plos One
|February 25, 2012
Summary
Spider silk protein composition changes with diet. Spiders adjust amino acid content, particularly proline and glutamine, in their major ampullate (MA) silk when protein intake is limited, impacting silk properties.
Area of Science:
- Biochemistry
- Animal Behavior
- Materials Science
Background:
- Spider silk proteins (spidroins) like MaSp1 and MaSp2 vary in amino acid composition.
- Glutamine and proline are energetically expensive to synthesize.
- Orb web spiders may alter silk protein expression based on food availability.
Purpose of the Study:
- To investigate how protein-limited diets affect the amino acid composition and mechanical properties of spider major ampullate (MA) silk.
- To determine if spiders shift silk protein expression (MaSp1 vs. MaSp2) under nutritional stress.
Main Methods:
- Three spider species (Argiope aetherea, Cyrtophora moluccensis, Leucauge blanda) were fed varying protein solutions (high, low, none).
- Amino acid composition and mechanical properties of MA silk were analyzed after 10 days.
- Silk properties were compared between species and dietary treatments, accounting for evolutionary relationships.
Main Results:
- Protein-limited diets significantly decreased proline and glutamine in the MA silk of A. aetherea and L. blanda.
- Glutamine content in C. moluccensis silk was also affected by protein intake.
- Proline content in C. moluccensis MA silk did not significantly change with protein intake.
Conclusions:
- Protein limitation induces a shift towards silk proteins with lower glutamine and/or proline.
- Observed variations in proline and serine reduction challenge the simple MaSp model.
- Silk mechanical properties may be influenced by factors beyond MaSp expression, including spidroin orthologues and spinning processes.
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