Aberrant changes in post-translational modifications (PTMs) such as phosphate groups underlie a majority of human diseases. However, detection and quantification of PTMs for diagnostic or biomarker applications often require PTM-specific monoclonal antibodies (mAbs), which are challenging to generate using traditional antibody-selection methods. Here we outline a general strategy for producing synthetic, PTM-specific mAbs by engineering a motif-specific hot spot into an antibody scaffold. Inspired by a natural phosphate-binding motif, we designed and selected mAb scaffolds with hot spots specific for phosphoserine, phosphothreonine or phosphotyrosine. Crystal structures of the phospho-specific mAbs revealed two distinct modes of phosphoresidue recognition. Our data suggest that each hot spot functions independently of the surrounding scaffold, as phage display antibody libraries using these scaffolds yielded >50 phospho- and target-specific mAbs against 70% of target peptides. Our motif-specific scaffold strategy may provide a general solution for rapid, robust development of anti-PTM mAbs for signaling, diagnostic and therapeutic applications.

High-quality and complete reference genome assemblies are fundamental for the application of genomics to biology, disease, and biodiversity conservation. However, such assemblies are available for only a few non-microbial species^1-4. To address this issue, the international Genome 10K (G10K) consortium^5,6 has worked over a five-year period to evaluate and develop cost-effective methods for assembling highly accurate and nearly complete reference genomes. Here we present lessons learned from generating assemblies for 16 species that represent six major vertebrate lineages. We confirm that long-read sequencing technologies are essential for maximizing genome quality, and that unresolved complex repeats and haplotype heterozygosity are major sources of assembly error when not handled correctly. Our assemblies correct substantial errors, add missing sequence in some of the best historical reference genomes, and reveal biological discoveries. These include the identification of many false gene duplications, increases in gene sizes, chromosome rearrangements that are specific to lineages, a repeated independent chromosome breakpoint in bat genomes, and a canonical GC-rich pattern in protein-coding genes and their regulatory regions. Adopting these lessons, we have embarked on the Vertebrate Genomes Project (VGP), an international effort to generate high-quality, complete reference genomes for all of the roughly 70,000 extant vertebrate species and to help to enable a new era of discovery across the life sciences.