Alternative splice form of type II procollagen mRNA (IIA) is predominant in skeletal precursors and non‐cartilaginous tissues during early mouse development

Zac1 is a zinc finger transcription factor that elicits antiproliferative activity and is a potential tumor suppressor gene. Through a detailed spatiotemporal study by in situ hybridization of mouse embryos, we have found that Zac1 transcript is predominantly localized in developing chondrogenic tissue, in addition to the central nervous system as reported elsewhere. Zac1 is also expressed transiently in the myocardium, skeletal muscle, and basal aspect of the stratified embryonic epithelia. During cartilage development, the pattern of Zac1 expression is in close accordance with the distribution of type II collagen mRNA in mesenchymal condensation and prehypertrophic chondrocytes. In mouse ATDC5 cells undergoing in vitro chondrogenesis, the Zac1 mRNA is up-regulated in parallel with genes expressed in precartilage but the Zac1 expression is low when type II collagen mRNA is markedly increased in differentiated cells. Together, these results suggest that Zac1 is a potential regulatory gene involved in chondrogenic differentiation. Developmental Dynamics 229:340 -348, 2004.

Section: Discussionmentioning

confidence: 77%

Zinc finger protein Zac1 is expressed in chondrogenic sites of the mouse

Tsuda

Markova

Wang

et al. 2004

“…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).…”

Section: Resultsmentioning

confidence: 99%

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

Nalin

Greenlee

Sandell

1995

Self Cite

The developmental sequence of the embryonic joint has been well studied morphologically. There are, however, no definitive studies of cell function during joint development. In order to begin to understand the differentiation events that contribute to joint formation, we examined the expression of collagen mRNAs encoding types I, IIA, IIB, and XI. In situ hybridization was performed on chicken embryo hind limb buds and digits from day 7 to day 18 (Hamburger and Hamilton stages 3144). In the day 7 (stage 31) limb bud, there was a condensation of mesenchyme forming the primitive tarsal and metatarsal bones that showed abundant expression of type IIA procollagen message, but no type IIB or type al(X1) message. By day 8 (stage 33), co-expression of types IIA, and type XI procollagen mRNAs was observed in the condensations, with expression of IIB restricted to early chondrocytes with metachromatically staining matrix. At this stage, DNA fragmentation characteristic of apoptosis was observed in cells near the midline of the interzone region between the developing anlagen, and in areas between and around the individual digits of the paddle. The presumptive apoptotic cells were more numerous at day 9 (stage 35), and were not found in the developing joint at subsequent time points, including the initiation of spatial cavitation of the joint. From days 11-18, type IIA procollagen mRNA was expressed in flattened cells at the surface of the anlagen, and in the perichondrium and in the developing joint capsule: type IIB mRNA message was found only in chondrocytes. Type XI mRNA was expressed by all type 11-expressing cells. Alpha l(1) mRNA was expressed early by cells of the interzone and capsule, but as cavitation progressed, the type I expressing cells of the interzone merged with the superficial layer of the articular surface. Thus, at the time of joint cavitation, there was a distinct pattern of expression of procollagen messages at the articular surface, with type I being outermost, followed by morphologically similar cells expressing type IIA, then chondrocytes expressing type IIB. The progenitor cells expressing type IIA message define a new population of cells. These cell populations contribute to the molecular heteroge-0

“…Procollagen IIA contains the second exon of the procollagen I1 gene and is only expressed in chondroprogenitor cells (Sandell et al, 1991(Sandell et al, , 1994. The comparison showed that in all locations the expression of the chondroprogenitor cell specific procollagen IIA and M-twist were mutually exclusive.…”

Section: -Dmentioning

confidence: 99%

Expression of M‐twist during postimplantation development of the mouse

Füchtbauer

1995

158

101

The murine homologue of the Drosophila twist gene has been shown to be essential for head mesenchyme formation and to act as an inhibitor of muscle differentiation. This paper presents a detailed analysis of M-twist expression patterns from day 7 post coitum ( p . 4 to day 18 P.c., indicating a more general function of the M-twist gene. At day 7 P.c., M-twist is expressed in the mesoderm outside the primitive streak. Later M-twist message is predominantly found in the somites, the head mesenchyme, the branchial arches, the limbs, and in the mesenchyme underneath the epidermis. Beginning at day 8 P.c., M-twist is mainly expressed in undifferentiated cells committed to muscle and cartilage development: this expression is consistent with a suggested role of M-twist in inhibiting overt muscle and cartilage differentiation. However, during organogenesis, M-twist is expressed in several areas of mesenchyme-epithelia interactions, suggesting additional tissue specific functions. 0 1995 Wiley-Liss, Jnc.