Stegodyphus lineatus
The act of reproduction, regarding the female, leads to an increase of digestive enzymes. This allows her to eat more prey and to stock more nutrients. The digestive enzymes then start to digest the inside of the organism itself, except for the heart, guts, and mostly the ovaries. Once the offspring are born, and until the mother dies, the mother regurgitates for two weeks the fluids stocked inside as highly nutritive food for the progeny. Ninety-five per cent of the mother's mass is digested by the offspring. They will grow to three times their original size between their birth and dispersion. During the period when female spiders are caring for their hatched offspring, the mothers do not eat, and their offspring only eat the food that the mother regurgitates along with the mother's body at the end of this time.
Restriction enzyme
Type III restriction enzymes (e.g., EcoP15) recognize two separate non-palindromic sequences that are inversely oriented. They cut DNA about 20–30 base pairs after the recognition site. These enzymes contain more than one subunit and require AdoMet and ATP cofactors for their roles in DNA methylation and restriction digestion , respectively. They are components of prokaryotic DNA restriction-modification mechanisms that protect the organism against invading foreign DNA. Type III enzymes are hetero-oligomeric, multifunctional proteins composed of two subunits, Res and Mod. The Mod subunit recognises the DNA sequence specific for the system and is a modification methyltransferase; as such, it is functionally equivalent to the M and S subunits of type I restriction endonuclease. Res is required for restriction digestion , although it has no enzymatic activity on its own. Type III enzymes recognise short 5–6 bp-long asymmetric DNA sequences and cleave 25–27 bp downstream to leave short, single-stranded 5' protrusions. They require the presence of two inversely oriented unmethylated recognition sites for restriction digestion to occur. These enzymes methylate only one strand of the DNA, at the N-6 position of adenosyl residues, so newly replicated DNA will have only one strand methylated, which is sufficient to protect against restriction digestion. Type III enzymes belong to the beta-subfamily of N6 adenine methyltransferases, containing the nine motifs that characterise this family, including motif I, the AdoMet binding pocket (FXGXG), and motif IV, the catalytic region (S/D/N (PP) Y/F).