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--- ecdysteroid_metabolism [2025/07/25 06:10] – external edit 127.0.0.1
+++ ecdysteroid_metabolism [2025/09/12 06:19] (current) – renefeyereisen
@@ Line 14: / Line 14: @@
 The reactions in ecdysteroid biosynthesis from sterol precursors are generally considered to be structured in a linear pathway: {{ ::pathwayecdy.jpg?direct&300 |}}
-In this pathway as classical depicted, the sterol precursor would be the C27 cholesterol. In some insects, C28 or C29 sterols are used instead, leading to C24-methyl or ethyl-branched ecdysteroids. Furthermore, the product of the [[cyp307page|black box]] depicted here is a 3-hydroxysterol, but in some insects it may be a 3-ketosterol, with the 3 keto group reduced during or after ecdysone production. P450 genes currently known to catalyze the steps depicted are mentioned in backets.
+In this pathway as classical depicted, the sterol precursor would be the C27 cholesterol. In some insects, C28 or C29 sterols are used instead, leading to C24-methyl or ethyl-branched ecdysteroids. Furthermore, the product of the [[cyp307page|black box]] depicted here is a 3-hydroxysterol, but in some insects it may be a 3-ketosterol, with the 3 keto group reduced during or after ecdysone production. P450 genes currently known to catalyze the steps depicted are mentioned in brackets.
 The origin of the P450 genes involved in ecdysteroid biosynthesis is of great evolutionary importance, as one might expect “Ecdysozoa” to be capable of making a molting hormone. However, the presence of ecdysteroids, or indeed of the ecdysteroidogenic P450s, is clearly not a synapomorphy (a shared derived trait that indicates a common ancestry) of “Ecdysozoa”. For instance the well-known nematode model //Caenorhabditis elegans// has //no// ecdysteroids and //none// of the P450s needed to make them.