Gene reg비 at i o n during the human craniofacial development is not well understood In effort to understand n ewly identifï ed genes that may play role(s) in the human craniofacial development, non-redundan t genes were isolated from the s ubtracted cDNA libra ry of human embryonal craniofacial tissues and examined their possible structu ral rolc in parallcl with thosc gcncs from isolatecl human c h o nclroc)πes cDNA library. Fifty genes were init ia ll y chosen from 398 clones iso latecl were used for selective dominant expression in both chondrocytes and the craniofacial sections of 10 weeks old human embryo by in situ hybridization method. Based upon the high levels 。f expression, we have identifi ecl seven unknown genes; ch89, ch96. ch129. ch 153. ch 276 ch285. and ch334 . In 。rder to unde rs tancl the possi ble role of these genes‘ the structural simulation of the expressed proteins were constructecl by Sybyl 6.6 program. Ch 276 gene was same with a clone, c14 0 1' f173. registered in GenBank(NM_022489) a nd is composed 0 1' 323 amino acids having a reverse s ignaling domain from the extra- cellular matrix(C-terminal) to cell membrane(N-terminal) and 12 turns of helical structure. Gene protein also r etains a famil iar fïbronectin binding domain(RGD). three s ites 0 1' Ca ion binding motifs. cAMP- and cGMP-dep endent protein kinase phos phorylation site, two regions of protein kinase C phosphorylation s ites. glyco- saminoglycan attachment s ite ancl N-glycosylation site. transmembrane and Al kaline Phosphatase active s ite domains This newly iclentifï ed human protein from human choncl rocytes cDNA library appearecl to be related to a known calcification s ignaling protein. was named as Ca lsin(Ch276) . Ch153 appeared to be related a family of anti-microbial peptide acting as an inflammation mediator and Ch334 clone as a zinc finger protein whose expression in creases in human adult ti ssue‘ These results suggest that these novel genes ident i!ï ed from human chondrocytes rnay provide a new path 0 1' embryonic cartilage development and human craniofacial development.

Given a protein, it is often necessary to study its geometric and physicochemical properties for studying its structure and predicting funtions of a protein. In this case, a connolly surface of a protein plays important roles for these purpose. A protein consists of a set of amino acids and a set of atoms comprise an amino acide. Since an atom can be represented by a hard 3D sphere in van der Waals model, a protein is usually modeled as a set of 3D spheres. In this paper, we present the algorithm for computing a connolly surface using Euclidean Voronoi diagram atoms of a protein. The algorithm initially locates the exterior aotms of a protein where connolly surface patches exist and computes the patches by tracking their boundary curves. Since a Euclidean Voronoi diagram is uniquely defined independent of probe radius different from other geometric structures, the connolly surfaces defined by probes of different radii can be computed without re-computing the Euclidean Voronoi diagram.