Expression of Muc19/Smgc Gene Products During Murine Sublingual Gland Development: Cytodifferentiation and Maturation of Salivary Mucous Cells
Expression of Muc19/Smgc Gene Products During Murine Sublingual Gland Development: Cytodifferentiation and Maturation of Salivary Mucous Cells
复制标题
DOI：
10.1369/jhc.2008.952853
复制
发表时间：
2009-04-01
影响因子：
3.2
通讯作者：
Culp, David J.
中科院分区：
文献类型：
--
作者：
Das, Biswadip;Cash, Melanie N.;Culp, David J.
Muc 19/Smgc表达两种剪接变体，Smgc（颌下腺蛋白C）和Muc 19（粘蛋白19），后者是分化的小鼠舌下粘液细胞的主要外分泌产物。最近在新生儿舌下腺中检测到SMGC的转录本，表明SMGC蛋白在初始唾液粘液细胞细胞分化过程中表达。因此，我们比较了Smgc和Muc 19的转录本和翻译产物在舌下腺中的发育表达。我们发现SMGC在最初的终端灯泡丰富的表达，随着Muc 19表达的增加，随后减少。在出生后的腺体扩张过程中，SMGC存在于假定的新形成的腺泡细胞中，然后持续存在于假定的腺泡干细胞中。在出生后的前3周，粘蛋白水平增加了7倍，转录水平几乎没有变化，而在出生后的第21天和第28天，Muc 19 mRNA和杂合RNA增加了3倍。我们的集体研究结果表明，从SMGC的直接过渡到Muc 19表达在早期粘液细胞的细胞分化，并进一步表明在Muc 19/Smgc转录，选择性剪接和翻译的发育调控的变化。Muc 19/Smgc基因表达的这些变化描绘了多个阶段的唾液粘液细胞的细胞分化和随后的成熟过程中，通过出生后的第一个4周的胚胎腺发育。（J Histochem Cytochem 57：383-396，2009）
Muc19/Smgc expresses two splice variants, Smgc (submandibular gland protein C) and Muc19 (mucin 19), the latter a major exocrine product of differentiated murine sublingual mucous cells. Transcripts for Smgc were detected recently in neonatal sublingual glands, suggesting that SMGC proteins are expressed during initial salivary mucous cell cytodifferentiation. We therefore compared developmental expression of transcripts and translation products of Smgc and Muc19 in sublingual glands. We find abundant expression of SMGC within the initial terminal bulbs, with a subsequent decrease as Muc19 expression increases. During postnatal gland expansion, SMGC is found in presumptive newly formed acinar cells and then persists in putative acinar stem cells. Mucin levels increase 7-fold during the first 3 weeks of life, with little change in transcript levels, whereas between postnatal days 21 and 28, there is a 3-fold increase in Muc19 mRNA and heteronuclear RNA. Our collective results demonstrate the direct transition from SMGC to Muc19 expression during early mucous cell cytodifferentiation and further indicate developmentally regulated changes in Muc19/Smgc transcription, alternative splicing, and translation. These changes in Muc19/Smgc gene expression delineate multiple stages of salivary mucous cell cytodifferentiation and subsequent maturation during embryonic gland development through the first 4 weeks of postnatal life. (J Histochem Cytochem 57:383-396, 2009)