Molecular and structural facets of cell–cell adhesion have been extensively studied in monolayered epithelia. Here, we perform a comprehensive analysis of cell–cell contacts in a series of multilayered tissues in the Xenopus gastrula model. We show that intercellular contact distances range from 10 to 1,000 nm. The contact width frequencies define tissue-specific contact spectra, and knockdown of adhesion factors modifies these spectra. This allows us to reconstruct the emergence of contact types from complex interactions of the factors. We find that the membrane proteoglycan Syndecan-4 plays a dominant role in all contacts, including narrow C-cadherin–mediated junctions. Glypican-4, hyaluronic acid, paraxial protocadherin, and fibronectin also control contact widths, and unexpectedly, C-cadherin functions in wide contacts. Using lanthanum staining, we identified three morphologically distinct forms of glycocalyx in contacts of the Xenopus gastrula, which are linked to the adhesion factors examined and mediate cell–cell attachment. Our study delineates a systematic approach to examine the varied contributions of adhesion factors individually or in combinations to nondiscrete and seemingly amorphous intercellular contacts.

细胞 - 细胞粘附的分子和结构方面已在单层上皮细胞中进行了广泛研究。在这里，我们对非洲爪蟾中一系列多层组织中的细胞 - 细胞接触进行了全面分析原肠胚模型。我们表明，细胞间接触距离范围从 10 到 1,000 nm。接触宽度频率定义了组织特异性接触光谱，而粘附因子的敲除会改变这些光谱。这使我们能够从因素的复杂相互作用中重建接触类型的出现。我们发现膜蛋白多糖 Syndecan-4 在所有接触中起主导作用，包括狭窄的 C-钙粘蛋白介导的连接。Glypican-4、透明质酸、旁轴原钙粘蛋白和纤连蛋白也控制接触宽度，而且出乎意料的是，C-钙粘蛋白在广泛接触中起作用。使用镧染色，我们在爪蟾的接触中鉴定了三种形态不同的糖萼形式原肠胚，与检查的粘附因子有关并介导细胞 - 细胞附着。我们的研究描述了一种系统方法来检查粘附因子单独或组合对非离散和看似无定形的细胞间接触的不同贡献。