Comparison of lipid accumulation from simple prokaryotes to mammals
| Taxa | Lipid types | Long-term lipid storage cell or organ | Lipid droplet proteins | Tag synthesis | Lipolysis | Leptin |
| Bacteria | Polymeric lipids (PHA and PHV); TAG (in Mycobacterium, Rhodococcus and Dietzia) | Unicellular (in response to starvation) | Phasins | PHA synthase; WS/DGAT | HSL and MGL; do not have ATGL | None |
| Yeast | 50% TAG; 50% SE | Unicellular (in response to starvation) | No PAT proteins except for some species (e.g. M. anisopliae) | Acyl-CoA dependent (Dga1); acyl-CoA independent (Lro1) | MGL; do not have ATGL/HSL | None |
| Worms | High TAG, low SE | Specialized cells (i.e. intestinal, skin and hepato-pancreatic cells) | No PAT proteins; other lipid proteins exist (e.g. seipin, leipin and caveolin). | Y53G8B.2 | ATGL and HSL; do not have MGL | None |
| Flies | High TAG, low SE | Fat body | PAT proteins (Lsd-1 and Lsd-2) | Midway | ATGL and HSL; do not have MGL | Upd2 (?) |
| Fish | TAG and CE (in adipocytes) | Adipose organ and liver | PAT proteins; CIDE domain family proteins | DGAT1 and DGAT2 | ATGL, HSL and MGL | Expressed in fat and various other tissues |
| Amphibia | TAG and CE (in adipocytes) | Adipose organ and liver | PAT proteins; CIDE domain family proteins | DGAT1 and DGAT2 | ATGL, HSL and MGL | Expressed in fat and various other tissues |
| Reptiles | TAG and CE (in adipocytes) | Adipose organ and liver | PAT proteins; CIDE domain family proteins | DGAT1 and DGAT2 | ATGL, HSL and MGL | Expressed in fat and various other tissues |
| Mammals | TAG and CE (in adipocytes); mostly SE (in macrophages) | Adipose organ; subcutaneous adipose tissue | PAT proteins; CIDE domain family proteins | DGAT1 and DGAT2 | ATGL, HSL and MGL | Expressed predominantly in white adipose tissue |
For references see Boxes 1 and 2. PHA, polyhydroxyalkanoates, PHV, polyhydroxyvalerates; SE, sterol esters; CE, cholesterol esters; TAG, triacylglycerol.