A transcriptomics approach uncovers novel roles for poly(ADP-ribosyl)ation in the basal defense response in Arabidopsis thaliana.

Pharmacological inhibition of poly(ADP-ribose) polymerase (PARP) or loss of Arabidopsis thaliana PARG1 (poly(ADP-ribose) glycohydrolase) disrupt a subset of plant defenses. In the present study we examined the impact of altered poly(ADP-ribosyl)ation on early gene expression induced by the microbe-associate molecular patterns (MAMPs) flagellin (flg22) and EF-Tu (elf18). Stringent statistical analyses and filtering identified 178 genes having MAMP-induced mRNA abundance patterns that were altered by either PARP inhibitor 3-aminobenzamide (3AB) or PARG1 knockout.

Folate synthesis in plants: the p-aminobenzoate branch is initiated by a bifunctional PabA-PabB protein that is targeted to plastids.

It is not known how plants synthesize the p-aminobenzoate (PABA) moiety of folates. In Escherichia coli, PABA is made from chorismate in two steps. First, the PabA and PabB proteins interact to catalyze transfer of the amide nitrogen of glutamine to chorismate, forming 4-amino-4-deoxychorismate (ADC).

LeCTR1, a tomato CTR1-like gene, demonstrates ethylene signaling ability in Arabidopsis and novel expression patterns in tomato.

LeCTR1 was initially isolated by both differential display reverse transcriptase-polymerase chain reaction screening for tomato (Lycopersicon esculentum) fruit ethylene-inducible genes and through homology with the Arabidopsis CTR1 cDNA. LeCTR1 shares strong nucleotide sequence homology with Arabidopsis CTR1, a gene acting downstream of the ethylene receptor and showing similarity to the Raf family of serine/threonine protein kinases. The length of the LeCTR1 transcribed region from ATG to stop codon (12,000 bp) is more than twice that of Arabidopsis CTR1 (4,700 bp).