Alternatively spliced type II procollagen mRNAs define distinct populations of cells during vertebral development: differential expression of the amino-propeptide.

Abstract

Abstract. Type II collagen is a major component of cartilage providing structural integrity to the tissue. Type II procollagen can be expressed in two forms by differential splicing of the primary gene transcript. The two mRNAs either include (type IIA) or exclude (type IIB) an exon (exon 2) encoding the major portion of the amino (NH2)-propeptide (Ryan, M. C., and L. J. Sandell . 1990. J. Biol. Chem. 265 :10334-10339) . The expression of the two procollagens was examined in order to establish a potential functional significance for the two type II procollagen mRNAs . First, to establish whether the two mRNAs are functional, we showed that both mRNAs can be translated and the proteins secreted into the extracellular environment . Both proteins were identified as type II procollagens . Secondly, to test the hypothesis that differential expression of type II procollagens may be a marker for a distinct population of cells, specific procollagen mRNAs were localized in tissue by in situ hybridization to oligonucleotides spanning the exon junctions . Embryonic vertebral column was chosen as a source of tissue undergoing rapid chondrogenesis, allowing the examination of a variety of cell types related to cartilage . In this issue, each procollagen mRNA had a distinct tissue distribution during chondrogenesis with type IIB expressed in chondrocytes and type IIA ex-YPE II collagen is the predominant collagenous component of cartilage composing >50 % of the extracellular matrix . Like type I collagen, the most abundant col lagen in vertebral organisms, it is an interstitial collagen' synthesized as a procollagen monomer, assembled into molecular trimers and processed extracellularly to remove NH2-and COON-terminal extension propeptides . The interstitial collagen monomer contains a non-interrupted Gly-XY protein domain of -1,014 amino acids, flanked by the globular propeptides . The COOH-terminal propeptide of ti 275 amino acids is connected to the main triple helix by a short telopeptide, is highly conserved between interstitial collagens, and is thought to be involved in initiation of trimer formation .The NH2-terminal propeptide shows more structural and sequence diversity among the interstitial collagens, but generally consists of a short globular domain followed by a cysteine-rich domain, a Gly-XY domain of40-60 residues, and a short connecting telopeptide (Sandell and Boyd, 1990) . It

Collagen gene expression during development of avian synovial joints: Transient expression of types II and XI collagen genes in the joint capsule

“…The a1 type XI oligonucleotide hybridized to a band of approximately 6.5 kb and the control a1 type I oligonucleotide probe hybridized with two RNA bands of approximately 5.3 and 7.1 kb. As a control for specificity of the type I, IIA, and IIB collagens, probes were hybridized to tissues where the distribution could be predicted by previous results from our laboratory (Sandell et al, 1991(Sandell et al, , 1994 and others (Nah and Upholt, 1991) (Fig. 2).…”

Scleraxis is Required for Differentiation of the Stapedius and Tensor Tympani Tendons of the Middle Ear

“…pdf. The following probes were used: the Scx fulllength probe (Brown et al 1999) for tendon and ligament progenitors and differentiated cells within these connective tissues; the Atonal homolog 1 probe (Helms and Johnson 1998) for sensory hair cells; and the Acan probe for chondrocytes (Sandell et al 1991).…”

“…The Acan probe (Sandell et al 1991) was used as a convenient marker for chondrocytes that facilitated identification of the developing ossicles and cartilaginous capsule of the cochlea (Hwang and Wu 2008) (Fig. 5C, F).…”

Expression patterns of hedgehog signaling peptides in naturally acquired equine osteochondrosis

“…Statistical analysis Paraformaldehyde fixed OC and normal osteochondral blocks were decalcified and sectioned, prior to processing by in situ hybridization as described by Sandell [24]. Slides were delipidated in xylene, treated with acetic anhydride (0.25% in 0.1 M triethanolamine), dehydrated in a graded series of alcohols, and air dried.…”