Kondaiah P et al. (1990), Identification of a novel transforming growth f...

XB-ART-26140

J Biol Chem January 15, 1990; 265 (2): 1089-93.

Identification of a novel transforming growth factor-beta (TGF-beta 5) mRNA in Xenopus laevis.

Kondaiah P , Sands MJ , Smith JM , Fields A , Roberts AB , Sporn MB , Melton DA .

Abstract
A novel transforming growth factor-beta (TGF-beta) mRNA of about 3.0 kilobases, which encodes a putative protein of 382 amino acids, has been identified in amphibians by cDNA cloning. This mRNA, which we designate as TGF-beta 5, is developmentally regulated and highly expressed beginning at early neurula (stage 14) and in many adult tissues in Xenopus laevis. Following the first methionine, the putative precursor protein has a hydrophobic region, approximately 22 amino acids long, which probably represents a signal sequence, similar to that found in TGF-beta s 1-3. The precursor also has potential sites for glycosylation, integrin binding (RGD), and a tetrabasic amino acid (RKKR) site for potential cleavage of the precursor peptide to a biologically active protein. The putative mature protein consists of 112 amino acids with 9 cysteines and has 76, 66, 69, and 72% identity to TGF-beta s 1-4, respectively.

PubMed ID: 2295601
Article link: J Biol Chem

Species referenced: Xenopus
Genes referenced: tgfb1

Article Images: [+] show captions

	FIG. 1. A, description of clone XCB4 and the sequencing strategy. The hatched region represents the precursor protein, whereas the shaded area represents the mature protein of 112 amino acids. The sequencing strategy is depicted by +. B, nucleotide and deduced amino acid sequence of XC(34. Nucleotides are numbered on the left side of the sequence. Amino acids are numbered on top of the sequence. The putative signal peptide is marked with a double ouerline. Three potential glycosylation sites are represented by a single ouerline. The potential integrin binding site (RGD), conserved in all TGF-Bs, with the exception of TGF-P2, is indicated by a split ouerline. The putative tetrabasic cleavage site is represented by a heavy bar. The mature peptide of 112 amino acids is shown as a boxed-in region. The potential polyadenylation signals (AATAAA) are underlined.
	FIN:. 2. A, comparison of the amino acid sequences of TGF-ps l- 5. The sequences of TGF-Bs l-4 have been obtained from the published reports (l-4). The respective TGF-0s are designated on the left side of each line. Amino acids are numbered on top with respect to the sequence of TGF-65. Amino acid residues conserved in all 5 TGF- /fs are represented by a +. An asterisk (*) represents the cysteines conserved in all five TGF+s. Underlines represent the potential Nlinked glycosylation sites (NXS/T), and the potential integrin binding sit,e (RGD) is shown by -+ +. R, comparison of the amino acid sequences of the putative mature protein of TGF-05 and the putative mature protein of Vgl (5). Respective proteins are indicated on the left side of the lines. Amino acids numbered on top and at the bottom correspond t.o the respective proteins. A “:” represents the conserved amino acid.
	IG. 3. A, Northern blots showing hybridization to RNA isolated from various developmental stages of X. laeuis. Each lane contains poly(A’) RNA from five embryo equivalents. The top panel shows hybridization with “LP-labeled antisense TGF-05 RNA, the bottom panel with “‘P-labeled antisense Vgl RNA. Size markers show that the TGF-85 transcript is about 3.0 kb; the Vgl transcript is about 2.8 kb. B, Northern blot analysis showing hybridization of “‘P-labeled TGF-45 cDNA to RNAs derived from various tissues of adult X. laeuis and from XTC cells. Each lane contains 15 pg of total RNA, except lane 6, which has 5 pg. RNAs were resolved in 1.2% agarose gels containing 2.2 M formaldehyde in 0.04 M MOPS buffer (pH 7.0). Respective tissues are labeled above each lane.