Previously we have highlighted proteins expressed in the human neural retina. This week's article emphasizes the cellular structure and molecular dynamics of the lens.

The main function of the lens is to focus light on the retina. The passage of light through the cornea, lens and vitreous all the way to the retinal layer of the eye is only possible due to transparency of the tissue. Although the lens is very protein-rich, light absorption and light scattering in the lens is minimal.

The lens comprises non-diving lens cells which are mainly composed of ordered proteins called crystallins...Read more

Melanoma is a common form of cancer in the skin and among skin cancers it is the most deadly form. Melanoma originates from cells of melanocytic origin and most typically begins as a small intraepidermal tumor (melanoma in situ). As the tumor continues to grow and progress, tumor cells invade the epidermis and eventually spread to regional lymph nodes and subsequently via hematogenic spread to distant organs. Tumor thickness of the primary tumor is the most important determining prognostic factor and thus is early discovery of key importance for survival.

The cancer image of the month shows skin with growth of a cutaneous melanoma...Read more

The Cell Atlas database was just recently released with data on more than 12.000 proteins and mapping to 30 organelles. Today, the scientific findings are published in Science in "A subcellular map of the humanproteome".

The cell is a complex entity that carries out multiple functions. In order to do this, the different parts of the cells are organized in structures, called organelles. By investigating the organelles and its proteome, and to understand how the proteins vary over time and space we can truly begin to understand human biology on a detailed level...Read more

Today, we are back in the Tissue Atlas facilities at the Rudbeck lab in Uppsala. Borbala Katona and Maria Aronsson are research engineers in the group working with microscopy and annotation of stained tissues, which we described last week.

Borbala Katona has a bachelors degree in biomedicine and a masters degree in infectious medicine and has been working within the Human Protein Atlas since 2014.

Maria Aronsson has a masters degree in medical biology from Linköping University and joined the Human Protein Atlas in 2012...Read more

Today, we start a "mini-series" about our Tissue Atlas here at the blog. Join us on a tour through the lab, meet some of the people working there, and see some really nice images produced by the scientists.

All the work on our Tissue Atlas is done at our Uppsala site, with Cecilia Lindskog as site director. You can learn all about her in one of our previous blog posts.

First we meet research engineer IngMarie Olsson who is group leader for the Tissue Microarray Production, Immunohistochemistry, and Scanning-group...Read more

Today, it is time for the first image of the week from the Cancer Atlas!

Lung cancer is one of the deadliest and most common forms of human cancer. Different forms of lung cancer exist and non-small cell lung cancer is the most common form. The cancer image this week is selected from such a lung cancer that has been immunohistochemically stained for the proliferation marker Ki-67 (MKI67). Ki-67 is the most commonly used immunohistochemical marker in rutin cancer diagnostics. The Ki-67 antigen is expressed in all cell nuclei that are active in the cell cycle and thus positive staining in a tumor cell population reflects the level of proliferation in that particular cancer...Read more

In two recent publications the group of Fredrik Pontén in Uppsala has identified two very strong, independent biomarkers for the prognostic stratification of breast cancer and renal cell carcinoma.

Renal cell carcinoma is the most common type of cancer affecting the kidney and there is an unmet clinical need for better prognostic and diagnostic tools for it. Diagnosis and subtyping of renal cell carcinoma are achieved through the morphological analysis of tumor sections. The application of immunohistochemistry can reveal important additional clues during the diagnostic work-up...Read more

In a recent publication in Endocrinology, researchers from the Human Protein Atlas have performed a comprehensive analysis of the gene expression landscape of the adrenal glands to define genes with different degrees of "specific" expression compared to 31 other normal human organs and tissue types. The analysis showed that only 253 genes (approximately 1% of all putative protein coding genes) showed some level of adrenal gland specific expression pattern.

The adrenal gland is a composite endocrine organ with vital functions that include the synthesis and release of glucocorticoids and catecholamines...Read more

In January 2015, the Tissue-based map of the human proteome by Uhlén et al was published. According to Google Scholar, the paper already has more than 400 citations. In a recent editorial by Cecilia Lindskog, the potential utility of the Human Protein Atlas and the Tissue-based map is reviewed.

Cecilia Lindskog is site director of the Tissue Atlas, and you can read more about her and the Tissue Atlas in this blog post from May this year...Read more

Time has come for the second interview with a researcher within the Human Protein Atlas project. Today we meet Cecilia Lindskog, site director of the Tissue Atlas.

– I have a Master of Science in Biomedicine and a Doctor of Philosophy in pathology from the Faculty of Medicine, Uppsala University. I joined the Human Protein Atlas project in 2006, and also have industry experience in the biotechnology industry, from Oncomark Ltd, Dublin, Ireland.

Cecilia Lindskog´s main research interests have always been understanding the biology and functions of different organs, and the underlying mechanisms leading to cancer and other diseases...Read more

Systematic antibody validation with siRNA for the Human Protein Atlas

Antibodies are among the most frequently used tools for basic research and clinical assays. For antibodies used in therapy or diagnostics, there are well-defined and strict guidelines that must be complied with before approval for clinical assays. For research antibodies, such guidelines have not yet been developed, despite the importance of demonstrating that they are specific, selective, and yield reproducible results in the immunoassay for which they are to be used...Read more

Version 14 of The Human Protein Atlas includes a new type of validation of antibodies that are used for determining the subcellular localization of a protein.

A set of antibodies have been analyzed in transgenic cell lines expressing GFP-tagged target protein at near-endogenous levels to confirm that the antibodies are capable of binding the target protein. The approved antibodies are then used to determine the subcellular localization of endogenous protein in a selection of cell lines. A high validation score is assigned to those genes where the same location(s) are observed for both tagged protein and protein detected using labelled antibody in non-transfected cells...Read more

Immunofluorescence and fluorescent-protein tagging show high correlation for protein localization in mammalian cells

The Human Protein Atlas applies antibodies for a variety of applications to map protein expression in different tissues and also at the subcellular level. Within the subcellular protein atlas, immunofluorescence (IF) is used to uncover the localization of proteins to different organelles. To ensure an accurate localization of each and very protein, the antibodies have to be specific to their target protein...Read more