Pneumosyytti I ei lisäänny mutta Pneumosyytti II voi tuottaa myös tyyppi I solua.

https://pubmed.ncbi.nlm.nih.gov/30865885/

Abstract

Lung alveolar type I cells (AT1) and alveolar type II cells (AT2) regulate the structural integrity and function of alveoli. AT1, covering ∼95% of the surface area, are responsible for gas exchange, whereas AT2 serve multiple functions, including alveolar repair through proliferation and differentiation into AT1. However, the signaling mechanisms for alveolar repair remain unclear. Here, we demonstrate, in Pseudomonas aeruginosa-induced acute lung injury in mice, that non-canonical Notch ligand Dlk1 (delta-like 1 homolog, DLL1) is essential for AT2-to-AT1 differentiation. Notch signaling was activated in AT2 at the onset of repair but later suppressed by Dlk1. Deletion of Dlk1 in AT2 induced persistent Notch activation, resulting in stalled transition to AT1 and accumulation of an intermediate cell population that expressed low levels of both AT1 and AT2 markers. Thus, Dlk1 expression leads to precisely timed inhibition of Notch signaling and activates AT2-to-AT1 differentiation, leading to alveolar repair.

Keywords: Dlk1; Notch; alveoli; lung; progenitor type II cell.

Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reser


Dlk1 (14q32.2 )

Entrez Gene Summary for DLK1 Gene

This gene encodes a transmembrane protein that contains multiple epidermal growth factor (EGF) repeats that functions as a regulator of cell growth. The encoded protein is involved in the differentiation of several cell types including adipocytes. This gene is located in a region of chromosome 14 frequently showing unparental disomy, and is imprinted and expressed from the paternal allele. A single nucleotide variant in this gene is associated with child and adolescent obesity and shows polar overdominance, where heterozygotes carrying an active paternal allele express the phenotype, while mutant homozygotes are normal. [provided by RefSeq, Nov 2015] GeneCards Summary for DLK1 (Delta Like Non-Canonical Notch Ligand 1) is a Protein Coding gene. Diseases associated with DLK1 include Idiopathic Central Precocious Puberty and Temple Syndrome. Among its related pathways are Notch Signaling Pathway (WikiPathways) and Signaling by GPCR. Gene Ontology (GO) annotations related to this gene include calcium ion binding. An important paralog of this gene is PEAR1.

 https://www.genecards.org/cgi-bin/carddisp.pl?gene=DLK1&keywords=Dlk1  
 Aliases for DLK1 Gene

• Delta Like Non-Canonical Notch Ligand 1 ^{2 3 5}
• Protein Delta Homolog 1 ^{3 4}
• DLK-1 ^{3 4}
• DLK ^{3 4}
• PG2 ^{3 4}
• Delta-Like 1 Homolog (Drosophila) ²
• Delta-Like Homolog (Drosophila) ²
• Preadipocyte Factor 1 ³

• Delta-Like 1 Homolog ³
• Fetal Antigen 1 ³
• Secredeltin ³
• Delta1 ³
• Pref-1 ³
• PREF1 ³
• FA1 ³
• ZOG ³