Literature summary for 5.4.99.8 extracted from

Gas-Pascual, E.; Berna, A.; Bach, T.J.; Schaller, H.
Plant oxidosqualene metabolism cycloartenol synthase-dependent sterol biosynthesis in Nicotiana benthamiana (2014), PLoS ONE, 9, e109156-64 .

Cloned(Commentary)

Cloned (Comment)	Organism
gene CAS1, sequence comparisons and phylogenetic tree	Nicotiana benthamiana
gene CAS1, sequence comparisons and phylogenetic tree, recombinant expression in the Saccharomyces cerevisiae mutant erg7 that lacks an endogenous lanosterol synthase. Upon galactose-induced expression of NtCAS1, yeast cells grown in the presence of exogenous ergosterol display a sterol profile that includes cycloartenol and four other sterols in addition to ergosterol. The major sterol is 24-methylene pollinastanol that accounts for 53% of the total and represents the most probable pathway end-product generated by the yeast steroidogenic machinery, apparently being versatile enough to accept cycloartenol as a substrate	Nicotiana tabacum

Cloned (Comment)

Organism

gene CAS1, sequence comparisons and phylogenetic tree

Nicotiana benthamiana

gene CAS1, sequence comparisons and phylogenetic tree, recombinant expression in the Saccharomyces cerevisiae mutant erg7 that lacks an endogenous lanosterol synthase. Upon galactose-induced expression of NtCAS1, yeast cells grown in the presence of exogenous ergosterol display a sterol profile that includes cycloartenol and four other sterols in addition to ergosterol. The major sterol is 24-methylene pollinastanol that accounts for 53% of the total and represents the most probable pathway end-product generated by the yeast steroidogenic machinery, apparently being versatile enough to accept cycloartenol as a substrate

Nicotiana tabacum

Protein Variants

Protein Variants	Comment	Organism
additional information	upon galactose-induced recombinant expression of NtCAS1, yeast cells grown in the presence of exogenous ergosterol display a sterol profile that includes cycloartenol and four other sterols in addition to ergosterol. The major sterol is 24-methylene pollinastanol that accounts for 53% of the total and represents the most probable pathway end-product generated by the yeast steroidogenic machinery, apparently being versatile enough to accept cycloartenol as a substrate. The sterol biosynthetic features of erg7::NtCAS1 are identical to the 9beta,19-cyclopropylsterol biosynthetic segment of protists, algae, or plants. In the presence of ergosterol, erg7 or erg7::NtCAS1 cells display a closely similar growth profile along a range of dilutions, whereas in the absence of ergosterol, only erg7::NtCAS1 is able to grow significantly when compared to yeast mutant erg7	Nicotiana tabacum
additional information	virus-induced gene silencing (VIGS) of CAS1 in Nicotianan benthamiana based on gene specific sequences from a Nicotiana tabacum CAS1. A morphogenetic inhibition is developed by PVX::CAS1 Nicotiana benthamiana leaves	Nicotiana benthamiana

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
(3S)-2,3-epoxy-2,3-dihydrosqualene	Nicotiana benthamiana	-	cycloartenol	-	r
(3S)-2,3-epoxy-2,3-dihydrosqualene	Nicotiana tabacum	-	cycloartenol	-	r

Organism

Organism	UniProt	Comment	Textmining
Nicotiana benthamiana	-	-	-
Nicotiana tabacum	A0A0A1ER86	-	-

Source Tissue

Source Tissue	Comment	Organism	Textmining
leaf	-	Nicotiana benthamiana	-
leaf	-	Nicotiana tabacum	-
TBY-2 cell	-	Nicotiana tabacum	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
(3S)-2,3-epoxy-2,3-dihydrosqualene	-	Nicotiana benthamiana	cycloartenol	-	r
(3S)-2,3-epoxy-2,3-dihydrosqualene	-	Nicotiana tabacum	cycloartenol	-	r

Synonyms

Synonyms	Comment	Organism
CAS1	-	Nicotiana benthamiana
CAS1	-	Nicotiana tabacum
NbCAS	-	Nicotiana benthamiana
NtCAS	-	Nicotiana tabacum

General Information

General Information	Comment	Organism
evolution	the enzyme belongs to the fammily of 2,3-oxidosqualene cyclases, OSCs	Nicotiana benthamiana
evolution	the enzyme belongs to the fammily of 2,3-oxidosqualene cyclases, OSCs	Nicotiana tabacum
metabolism	the plant sterol pathway exhibits a major biosynthetic difference as compared with that of metazoans. The committed sterol precursor is the pentacyclic cycloartenol (9beta,19-cyclolanost-24-en-3beta-ol) and not lanosterol (lanosta-8,24-dien-3beta-ol)	Nicotiana benthamiana
metabolism	the plant sterol pathway exhibits a major biosynthetic difference as compared with that of metazoans. The committed sterol precursor is the pentacyclic cycloartenol (9beta,19-cyclolanost-24-en-3beta-ol) and not lanosterol (lanosta-8,24-dien-3beta-ol)	Nicotiana tabacum
additional information	cell sterol profile is determind by GC-MS analysis	Nicotiana benthamiana
additional information	cell sterol profile is determined by GC-MS analysis	Nicotiana tabacum
physiological function	physiological relevance of CAS1 gene in plants, strict dependence on CAS1 of tobacco sterol biosynthesis	Nicotiana benthamiana
physiological function	physiological relevance of CAS1 gene in plants, strict dependence on CAS1 of tobacco sterol biosynthesis	Nicotiana tabacum