PPepDB-ID	"Peptide Name"	PMID	"Plant source"	"Plant Family"	"Peptide Family"	"Peptide function"	"Peptide function description"	"Activity against"	Sequence	"Sequence Length"	Validation	"Avg. Molecular wt(Da)"	"Monoisotopic molecular wt(Da)"	pI	Method	"Additional information"
PPepDB_5892	EXTN1_ARATH	--NA--	"Arabidopsis thaliana"	Brassicaceae	--NA--	Signaling-peptide	"Alternative splicing; Cell wall; Cell wall biogenesis/degradation; Complete proteome; Glycoprotein; Hydroxylation; Repeat; Secreted; Signal; Structural protein | Extensin-1 precursor (AtExt1) (AtExt4).Secreted, primary cell wall."	--NA--	KHYSPPPVYKSPPPPVKYYSPPPVYKSPPPPVKHYSPPPVYKSPPPPVKYMASFLVLAFSLAFVSQTTANYFYSSPPPPVKHYSPPPVYKSPPPPVKHYSPPPVYKSPPPPVKHYSPPPVYKSPPPPVKYYSPPPVYKSPPPPVYKSPPPPPVHHYSPPHQPYLYKSPPPPHYPPVVYHSPPPPVHYSPPPVVYHSPPPPVHYSPPPVVYHSPPPPVHYSPPPPVKHYSPPPVYKSPPPPVKHYSPPPVYKSPPPPVKHYSPPPVYKSPPPPVVVYHSPPPPVHYSPPPVVYHSPPPPKKHYEYKSPPPPVHYSPPTVYHSPPYSPPPVYKSPPPPVKHYSPPPVYKSPPPPVKYYSPPPVYKSPPPPVHYSP	373	"Experimental evidence at transcript level"	41555.23	41528.55	9.74	--NA--	"FUNCTION:Structural component which strengthens the primary cell wall.ALTERNATIVE PRODUCTS:Event=Alternative splicing; Named isoforms=2; Comment=Experimental confirmation may be lacking for some isoforms; Name=1; IsoId=Q38913-1; Sequence=Displayed; Name=2; IsoId=Q38913-2; Sequence=VSP_008897;TISSUE SPECIFICITY:Predominantly expressed in the roots. Not detected in the leaves, nor in flowers or flower buds. Wounding reverses this pattern, turning on the gene in the leaves and repressing it in the roots.DEVELOPMENTAL STAGE:Early expressed in the whole plant. Detected in the leaves of 2 and 4 weeks old rosettes, but not in 6-weeks- old rosettes. Detected specifically in roots from the mature plant (6-weeks old).INDUCTION:By wounding, water and cold stresses; in response to plant hormones 2,4-D, BAP, GA3, SA, MeJA and ABA treatment; in response to L-Ser, Hyp and L-Pro treatment.PTM:Extensins contain a characteristic repeat of the pentapeptide Ser-Pro(4). For this particular extensin, a typical repeat of Ser- Pro(3) is found. In both cases, the proline residues are hydroxylated and then O-glycosylated (arabinosylation).PTM:Synthetised as soluble proteins which become insolubilised in the cell wall through the intermolecular cross-linking of Tyr on adjacent monomers. Isodityrosine (IDT) stabilizes and makes rigid the part of the polypeptide where IDT functional sites are present.SIMILARITY:Belongs to the extensin family.SEQUENCE CAUTION:Sequence=AAA85899.1; Type=Miscellaneous discrepancy; Note=In cv. Landsberg erecta, absence of several repeats; "