Disease relevance of P5CS1

• Proline accumulation in response to water stress and salinity is preceded by a rapid increase of the mRNA level of delta 1-pyrroline-5-carboxylate synthase (P5CS) controlling the rate-limiting step of glutamate-derived proline biosynthesis [1].

High impact information on P5CS1

• Overexpression of Gm-CaM4 in Arabidopsis up-regulates the transcription rate of AtMYB2-regulated genes, including the proline-synthesizing enzyme P5CS1 (Delta1-pyrroline-5-carboxylate synthetase-1), which confers salt tolerance by facilitating proline accumulation [2].
• However, inhibition of protein synthesis by cycloheximide prevents the induction of AtP5CS2 mRNA accumulation, and blocks further increase of AtP5CS1 mRNA levels during the second, slow phase of salt-induction [1].
• Induction of AtP5CS1 mRNA accumulation in salt-treated seedlings involves an immediate early transcriptional response regulated by ABA signalling that is not inhibited by cycloheximide, but abolished by the deficiency of ABA biosynthesis in the aba1 Arabidopsis mutant [1].
• Gene AtP5CS1 mapped to chromosome 2-78.5 is expressed in most plant organs, but silent in dividing cells [1].
• Regulation of P5CS1 expression thus appears to play a principal role in controlling proline accumulation stimulated by ABA and salt stress in Arabidopsis [3].

Biological context of P5CS1

• Stress-responsive and developmental regulation of Delta(1)-pyrroline-5-carboxylate synthetase 1 (P5CS1) gene expression in Arabidopsis thaliana [4].
• Incompatible interactions lead to transcriptional activation of AtP5CS2, but not AtP5CS1, encoding the rate limiting enzyme in Pro biosynthesis pyrroline-5-carboxylate synthase (P5CS) [5].

Associations of P5CS1 with chemical compounds

• Delta(1)-Pyrroline-5-carboxylate synthetase 1 (P5CS1) is the rate-limiting enzyme in the biosynthesis of proline by Arabidopsis thaliana [4].

References