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Steroid Receptors in the Pregnant Uterus*
Published in Gabor Huszar, The Physiology and Biochemistry of the Uterus in Pregnancy and Labor, 2020
Hideki Sakamoto, Neil MacLusky, Frederick Naftolin
The role of these “nonreceptor” binding proteins in the modulation of steroid action during pregnancy is probably not confined to the bloodstream. There is evidence that the circulating steroid carrier proteins are in dynamic equilibrium between the intra-and extracellular compartments. Transcortin has been identified in rat uterus,37 as well as in human endometrial cells.38 In rats, albumin and α-fetoprotein have been demonstrated in uterine cells.39 The rabbit uterus synthesizes another steroid binding protein, uteroglobin, in response to P. This small secretory protein binds E and P with moderately high affinity and in the maximally induced state comprises 30 to 40% of the total uterine-secreted protein.40
Mammalian allergens
Published in Richard F. Lockey, Dennis K. Ledford, Allergens and Allergen Immunotherapy, 2020
Tuomas Virtanen, Marja Rytkönen-Nissinen
Fel d 1 is a glycoprotein with a molecular mass of 38 kDa [63]. It is a tetramer composed of two noncovalently linked heterodimers, each with a molecular mass of about 19 kDa. These dimers are composed of an 8-kDa chain 1 (α-chain) and 10-kDa chain 2 (β-chain), which are linked together covalently by three disulfide bonds. Chain 1 contains 70 amino acids, and the dominant forms of chain 2 contain 90 or 92 amino acids [64,65]. Chain 1 has a 29% amino acid identity with human uteroglobin, an anti-inflammatory protein (BLAST). Chain 2 has an amino acid identity of 39% with a putative human protein in a segment of 41 amino acids (BLAST). Both chains are classified as members of the secretoglobin (uteroglobin) family. Fel d 1 exists in several isoforms [63] and can be produced in a recombinant form. The three-dimensional structure of Fel d 1 is strikingly similar to that of uteroglobin and contains two cavities with potential for ligand binding [66].
Intestinal Chloride Secretion: Cyclic Amp and Ca2+ Interactions
Published in T. S. Gaginella, Regulatory Mechanisms — in — Gastrointestinal Function, 2017
Vincenzo Calderaro, Francesco Rossi
Glucocorticoid-induced lipocortins, a family of Ca2+- and phospholipidbinding proteins (for nomenclature see Reference 209), appeared to inhibit PLA2,210,211 but this effect is most likely due to sequestering of the phospholipase substrate rather than to a direct interaction with the phospholipase.212However, at the end of the last decade, antiflammins, peptides corresponding to a region of striking similarity between uteroglobin, a progesterone-induced rabbit secretory protein inhibitory for PLA2, and lipocortin I,213,214 appeared as a new and exciting therapeutic tool for control of inflammatory response.
Biological changes in C57BL/6 mice following 3 weeks of inhalation exposure to cigarette smoke or e-vapor aerosols
Published in Inhalation Toxicology, 2018
K. Monica Lee, Julia Hoeng, Sam Harbo, Ulrike Kogel, William Gardner, Michael Oldham, Eric Benson, Marja Talikka, Athanasios Kondylis, Florian Martin, Bjoern Titz, Sam Ansari, Keyur Trivedi, Emmanuel Guedj, Ashraf Elamin, Nikolai V. Ivanov, Patrick Vanscheeuwijck, Manuel C. Peitsch, Willie J. McKinney
Changes in BALF mediators were observed mainly in the 3R4F group (e.g. IP-10, MIP-1b) (Supplemental Figure S2 and Supplemental Table S3). Some trends were also observed in e-vapor groups; for example, GM-CSF and IL-7, albeit at very low levels, were down-regulated in all exposure groups compared to the Sham Control. For some mediators, changes in the 3R4F and e-vapor groups were in a different direction compared to the Sham Control: IL-6 and proMMP-9 were no different or slightly down-regulated in the e-vapor groups but up-regulated in the 3R4F group. To complement the MAP analysis, additional proteins were measured in BALF with targeted mass-spectrometry (PRM). Compared with the Sham Control, most changes were again observed with the 3R4F group (e.g. Mpo (PERM)), while no clear changes were detected in any of the e-vapor groups (Supplemental Figure S3 and Supplemental Table S3). Some qualitative trends were observed: uteroglobin/CC10 (UTER) tended to be slightly down-regulated in all treatment groups especially the 3R4F group. Serping1 (IC1) was slightly up-regulated in the Test-2 and 3R4F groups, while cathepsin S (CATS) was slightly up-regulated in the Carrier group. Plasma samples were analyzed for biomarkers of oxidative stress (MPO) and protease (MMP-12 and proMMP-9) but their levels were not different between any exposure group and the Sham Control.
N-terminal α-amino group modification of antibodies using a site-selective click chemistry method
Published in mAbs, 2018
De-zhi Li, Bing-nan Han, Rui Wei, Gui-yang Yao, Zhizhen Chen, Jie Liu, Terence C.W. Poon, Wu Su, Zhongyu Zhu, Dimiter S. Dimitrov, Qi Zhao
We synthesized a new 2-PCA derivative, 6-AM-2-PCA, that retains the capacity of 2-PCAs to react with N-terminal amino acids of proteins and form stable covalent bonds. In addition, 6-AM-2-PCA is capable of reacting with DBCO derivatives. Site-selectivity of 6-AM-2-PCA for N-terminal α-amines was confirmed by MS analysis. Modification efficiency can be determined by concentrations of free 6-AM-2-PCA. Further experiments demonstrated that 6-AM-2-PCA is able to modify proteins in a single step under physiological conditions that are moderate enough to permit biomolecular activities. MacDonald et al demonstrated that 2-PCA afforded 43% to 95% modification for different proteins.28 Notably, 33% of uteroglobin, a covalent homodimer, was singly modified at either of two N termini. Our studies demonstrated that 6-AM-2-PCA as a derivative of 2-PCA afforded >79% modification of anti-HER2 Fab with single and double labels. Similar to uteroglobin, we did not obtain the complete formation of double labels per anti-HER2 Fab even at 100-fold excess of reagents. Interestingly, half of bis-modified proteins formed hemiaminal products after the aldehyde-amine reaction. Our further study revealed that 6-AM-2-PCA mainly reacted to the N-terminus of anti-HER2 Fab heavy chain. Steric hindrance from the tertiary structure of the N-terminal region may affect selectivity to either heavy or light chains of the antibody. The 2-PCA method is specific for the native N termini of some antibodies.28 Therefore, it will be interesting to investigate reaction conditions of 6-AM-2-PCA for different antibodies in future studies.
Reaction products of hexamethylene diisocyanate vapors with “self” molecules in the airways of rabbits exposed via tracheostomy
Published in Xenobiotica, 2018
Adam V. Wisnewski, Jean Kanyo, Jennifer Asher, James A. Goodrich, Grace Barnett, Lyn Patrylak, Jian Liu, Carrie A. Redlich, Ala F. Nassar
We also analyzed the >3 kDa fraction of BAL fluid from HDI vapor-exposed rabbits using proteomic techniques to identify HDI-modified proteins and their sites of HDI conjugation. LC-MS/MS data identified one peptide with strong evidence of HDI modification in both exposed rabbits, E1 and E2 (Table 1, Figure 4 and Supplemental materials Figures S6-S8). This peptide comprises amino acids 63–70 of uteroglobin (aka Clara or club cell protein), with modification of the lysine at amino acid position 65 (K65) of the mature secreted protein, by partially hydrolyzed HDI (+142.11 kDa). The HDI-modified site is situated near uteroglobin’s C-terminus, in close proximity to a disulfide bond that bridges uteroglobin monomers. The side chain of uteroglobin K65 has been modeled to protrude from the surface (Bally & Delettre 1989), which may influence susceptibility to HDI conjugation, as shown in Figure 5. Two other sites of uteroglobin modification by HDI are suggested by the data, one in each of the two exposed rabbits, and include modification by partially hydrolyzed HDI (+142.11 kDa) and HDI cross-linking (+168.09 kDa) as shown in Table 1 and Supplemental materials Figures S6 and S7.