diff --git a/README.md b/README.md
index ca5958f..042d721 100644
--- a/README.md
+++ b/README.md
@@ -73,7 +73,7 @@ Note that install.sh extensively depends on apt-get, so it is unlikely
 to run without extensive modifications on non-Debian-based systems.
 
 Nucleus depends on TensorFlow.  By default, install.sh will
-install a CPU-only version of a stable TensorFlow release (currently 2.1).
+install a CPU-only version of a stable TensorFlow release (currently 2.2).
 If that isn't what you want, there are several other options that
 can be enabled with a simple edit to ``install.sh``.
 
@@ -87,9 +87,12 @@ bazel test -c opt $BAZEL_FLAGS nucleus/...
 
 ## Version
 
-This is Nucleus 0.5.4. Nucleus follows [semantic
+This is Nucleus 0.5.5. Nucleus follows [semantic
 versioning](https://semver.org/).
 
+New in 0.5.5:
+* Upgrade protobuf settings to support TensorFlow 2.2.0 specifically.
+
 New in 0.5.4:
 * Upgrade to protobuf 3.8.0 to support TensorFlow 2.1.0.
 * Add explicit .close() method to TFRecordWriter.
diff --git a/nucleus/pip_package/build_pip_package.sh b/nucleus/pip_package/build_pip_package.sh
index a3af0cd..3f4e156 100755
--- a/nucleus/pip_package/build_pip_package.sh
+++ b/nucleus/pip_package/build_pip_package.sh
@@ -1,5 +1,5 @@
 #!/bin/bash
-# Copyright 2018 Google LLC.
+# Copyright 2020 Google LLC.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@ set -x
 
 # When changing NUCLEUS_VERSION, be sure to also change it in
 # egg_files/PKG-INFO.
-NUCLEUS_VERSION="0.5.4"
+NUCLEUS_VERSION="0.5.5"
 PACKAGE_NAME="google_nucleus-${NUCLEUS_VERSION}"
 PYTHON_VERSION="3.5"
 
diff --git a/nucleus/pip_package/egg_files/PKG-INFO b/nucleus/pip_package/egg_files/PKG-INFO
index d05e7a2..ca7f01c 100644
--- a/nucleus/pip_package/egg_files/PKG-INFO
+++ b/nucleus/pip_package/egg_files/PKG-INFO
@@ -1,6 +1,6 @@
 Metadata-Version: 1.1
 Name: google-nucleus
-Version: 0.5.4
+Version: 0.5.5
 Summary: A library for reading and writing genomics data.
 Home-page: https://github.com/google/nucleus
 Author: The Genomics team in Google Brain